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Treaty between the United States of America and the Union of Soviet Socialist Republics on Strategic Offensive Reductions (START II)

START II complemented START I by attempting to establish further limits on strategic nuclear weapons for each party.

  • Ratified

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3 January 1993


26 September 1996

Ratified by US Senate

April 2000

Ratified by the Russian State Duma and Federation Council

14 June 2002

Russia Declares It Null and Void

Treaty Overview

Extension Protocol

  • Ratified by the Russian State Duma: 14 April 2000
  • Ratified by the Russian Federation Council: 19 April 2000
  • US Letter on Early Deactivation: 26 September 1997
  • Russian Letter on Early Deactivation: 26 September 1997

The US Senate Ratification Resolution included a provision requiring the president to seek Senate approval of any strategic arms cuts that would reduce the US strategic arsenal to below START I ceilings before START II entered into force. Russian State Duma START II Ratification Law required the US Senate to ratify the Extension Protocol and the 1997 ABM Demarcation Agreements for ratification instruments to be exchanged and for the Treaty to enter into force.

On 14 June 2002, the Russian Federation announced its withdrawal from START II due to US refusal to ratify the Treaty and to US withdrawal from the ABM Treaty. The Treaty is no longer in effect.

Treaty Obligations

START II complemented, rather than replaced, the earlier START I, in that the earlier Treaty’s provisions remain unchanged unless specifically modified by START II. START II was to remain in force for the duration of START I.

START II established a limit on strategic weapons for each Party, with reductions to be implemented in two phases. By the end of Phase I, the United States and Russia were to reduce their total deployed strategic nuclear warheads to 3,800-4,250, including no more than 2,160 warheads deployed on submarine-launched ballistic missiles (SLBMs), no more than 650 on heavy intercontinental ballistic missiles (ICBMs), and no more than 1,700-1,750 on SLBMs. By the end of Phase II, each Party’s total number of deployed strategic nuclear warheads was not to exceed 3,000-3,500. Of this number, no more than 1,700-1,750 were to be deployed on SLBMs. Phase II required the elimination of all heavy ICBMs and all ICBMs on multiple independently targetable re-entry vehicles (MIRVs) (although some of the latter were to be downloaded to one warhead).The MIRV ban did not apply to SLBMs.

Initially, Phase I was to be fully implemented within seven years of the entry into force of START I, and Phase II was to be fully implemented by 1 January 2003. However, these timeframes were extended to 31 December 2004 and 31 December 2007, respectively, by a Protocol to the Treaty signed by US and Russian representatives on 27 September 1997. In spite of this delay, both sides pledged to deactivate all weapons to be eliminated under START II by 31 December 2003. The fixed implementation deadline of START II made it unusual among arms control treaties, and the delays in ratifying it by both the United States and the Russian Federation, as well as the unexpectedly early entry into force of START I on 5 December 1994, required an extension to these deadlines.

START II modified START I missile “downloading” rules governing which MIRVed missiles may be converted to a single-warhead configuration. START II allowed each side to download two existing types of missiles by up to four warheads per missile, with no limit on the total number of missiles or warheads affected. Each side was also allowed to download 105 ICBMs by up to five warheads per missile. In practice, these conditions meant Russia may download 105 of its UR-100Ns [NATO designation SS-19 “Stiletto,” START designation RS-18], the only Russian in-service ICBM that qualified for downloading, and was to deactivate all of its 10-warhead RT-23UTTKh [NATO designation SS-24 “Scalpel,” START designation RS-22] ICBMs.

START II missile system elimination rules were generally similar to those of START I in that they required that the missile’s silo was to be eliminated or converted to carry a Treaty-permitted missile type. The sole exception to this rule was the R-36M [NATO designation SS-18 “Satan,” START designation RS-20] ICBMs, which were to be destroyed along with their silos. START II allowed 90 R-36M silos to be converted for use by single-warhead missiles, however, which meant that the Russian elimination quota was 64 out of 154 R-36M silos.

In contrast to START I, START II calculated nuclear warheads attributed to heavy bombers by counting the number of warheads each heavy bomber is actually capable of carrying. Additionally, START II allowed each side to convert up to 100 heavy bombers to conventional roles. Such bombers would not be counted against the START II warhead limit provided they had observable differences from nuclear-capable bombers of the same type and were not based at the same locations as nuclear-capable bombers. Each side was to convert such bombers to a nuclear role following a three-month notification but was not to subsequently reconvert them to a conventional role.

Verification and Compliance


Like the provisions of its predecessor, START II provisions would have been verified by on-site inspections, including observation of differences on heavy bombers converted to conventional roles, and missile and silo elimination or conversion. Silo conversions were also subject to inspection. START II provided for inspections in addition to those called for in START. START II provided for additional inspections to confirm the elimination of heavy ICBMs and their launch canisters, as well as additional inspections to confirm the conversions of heavy ICBM silo launchers. In addition, START II provided for exhibitions and inspections to observe the number of nuclear weapons for which heavy bombers were actually equipped and their relevant observable differences. These additional inspections were to be carried out according to the provisions of START unless otherwise specified in the Elimination and Conversion Protocol or in the Exhibitions and Inspections Protocol.


To provide a forum for discussion of implementation of START II, the Treaty established the Bilateral Implementation Commission (BIC). Through the BIC, the Parties could have resolved questions of compliance and agreed upon additional measures to improve the viability and effectiveness of the Treaty.


During a meeting in Helsinki in March 1997, US President Bill Clinton and Russian President Boris Yeltsin adopted a Joint Statement that committed both countries to begin START III negotiations as soon as START II entered into force. The two sides began consultations on strategic stability in the summer of 1997 and continued until the fall of 2000. During the September 1998 summit in Moscow, the two presidents reaffirmed their commitment to begin formal START III negotiations after Russia’s ratification of START II. In 2000 the United States and Russia exchanged draft START III texts.

The basic provisions of START III, as laid out in the Helsinki Joint Statement of 21 March 1997, included reducing the aggregate levels of strategic nuclear warheads to 2,000-2,500 per side, establishing strategic nuclear inventory transparency measures, ensuring irreversibility of the reductions, and making START I and II unlimited in duration. The Joint Statement also included language supporting confidence-building and transparency measures concerning long-range sea-launched cruise missiles and tactical nuclear weapons, which would be explored as separate issues in the START III context.

In 2000, the Russian Federation officially proposed a lower aggregate level ceiling of 1,000-1,500, a position which did not receive US support. Since the beginning of START III discussions, the Russian Federation made START III negotiations contingent on US support for the preservation of the ABM Treaty.




On 13 June, US President Bush declared that the US withdrawal from the ABM Treaty, which he had announced 6 months earlier in accordance with the Treaty’s provisions, was formally taking effect, thereby marking the end of the ABM Treaty. On 14 June, the Russian Federation announced its withdrawal from the START II Treaty due to US refusal to ratify the Treaty and to US withdrawal from the ABM Treaty.


Defense Minister Sergey Ivanov announced on 11 December that Russia would not begin implementing the provisions of START II until the United States ratified the Treaty. Ivanov said that since the United States had not yet ratified it, the Treaty had not entered into force and therefore Russia was not obligated to carry out the required reductions of its strategic forces.

During a press conference held on 19 December following the conclusion of a NATO conference in Brussels, Russian Defense Minister Sergey Ivanov stated that, as a result of the US decision to withdraw from the ABM Treaty, START II would never enter into force. According to Ivanov the US decision caused not only the “disappearance of the entire legal mechanism regulating the reductions of strategic offensive armaments,” but also undermined all existing nonproliferation agreements and nuclear testing treaties, and even the supplementary protocol to the Biological Weapons Convention.


The Duma ratified START II by a vote of 288-131 with four abstentions at its 14 April session. Ratification required 226 votes. The Federation Council, the upper house of the Russian Federal Assembly, ratified the Treaty on 19 April.

Vladimir Putin signed the START II Ratification Law on 4 May. The law was to enter into force on the date of its publication in the official government newspaper, Rossiyskaya gazeta. However, the Treaty itself was not to enter into force until the conditions contained in the ratification law were fulfilled.

On 10 May, the U.S. House Armed Forces Committee defeated a proposal to unilaterally reduce the strategic forces to START II levels before the treaty entered into force.


A summit meeting between Presidents Bill Clinton and Boris Yeltsin was held on 20 June in Cologne, Germany on the last day of the annual summit of the Group of Eight nations. The two presidents agreed to hold preliminary consultations on START III and to begin discussions on “possibly reopening” the 1972 ABM treaty on 17-19 August in Moscow. US Deputy Secretary of State Strobe Talbott will be the head of the US delegation to the talks. According to Sandy Berger, President Clinton’s national security adviser, this is the first time that Russia has agreed to discuss changes to the ABM Treaty. In the Russia-US joint statement released in Cologne, the two sides recognized the “fundamental importance” of the Treaty and reaffirmed their current obligations under Article XIII “to consider possible changes in the strategic situation that have a bearing on the ABM Treaty and, as appropriate, possible proposals for further increasing the viability of this Treaty.” The two governments also pledged to “do everything in their power to facilitate the successful completion of the START II ratification processes in both countries.” Despite the agreement to consider possible changes to the ABM Treaty, Russian Foreign Minister Igor Ivanov said that the US plan to deploy the nation-wide ABM system “is dangerous and can destroy the basis of strategic stability and the whole disarmament process” and expressed hope that “Russia and the US will be factors of stability and security.”



In its report START II: Prospects for Ratification released on 28 April, the Analytic Directorate of the Duma argued that START II should be ratified only if the Treaty is amended to include a series of supplemental proposals. The report recommended that the ratification legislation should encompass the principle of equal reduction for both Russian and US strategic forces. To justify its position, the report cited the conditions the US Senate added when it ratified START II in January 1996. The report echoed START II opponents’ criticism that the United States had secured for itself terms that allowed “reducing without destroying,” which would enable the United States to swiftly increase its nuclear strike potential should a crisis situation develop. US strategic nuclear forces rely heavily on SLBMs, from which some nuclear warheads must be removed, but not destroyed, under the terms of START II.

In an interview given on 12 May, Russian Foreign Minister Yevgeniy Primakov stated that any US economic sanctions against Russian companies suspected of selling missile technology to Iran would likely affect the chances of START II being ratified by the Duma. Referring to accusations that Russian firms are assisting the Iranian missile program, Primakov stated that “Russia does not seek to advance Iran’s missile industry,” and said that Russia had no reason “to encourage the creation of a missile with a range of 2,000 kilometers in Iran.” Primakov added, though, that he and Defense Minister Igor Sergeyev should be able to persuade Duma members to ratify the Treaty.

In a 45-minute meeting at the close of the G-8 summit with US President Bill Clinton in Birmingham, England on 17 May, Russian President Boris Yeltsin said that his administration would step up its efforts for START II ratification by Russia’s reluctant parliament. During the talks, Clinton again linked the timing of the next US-Russian summit with the ratification of START II, saying that he would like to hold a summit meeting in Moscow this year to discuss further arms reduction talks, but adding that Washington would first like to see the Russian Federal Assembly ratify START II.

In a resolution adopted on 21 August, the Duma voiced “deep concern in connection with the US missile strikes at targets in Sudan and Afghanistan,” which were launched by Washington in retaliation for the August 1998 bombings of US embassies in Nairobi, Kenya and in Dar Es Salaam, Tanzania. The non-binding resolution, passed 264-0 with two abstentions, argued that the missile strikes violated international law and the UN Charter, and termed them an act of aggression. The resolution asserted that such action on the part of the United States would prompt deputies to “weigh most thoroughly all the pluses and minuses of ratification of the START II Treaty.” The Duma has often tried to link its ratification of START II to US foreign policy regarding other issues, including NATO enlargement, Iraq, Bosnia, and Kosovo.

At their 1-3 September summit meeting in Moscow, Presidents Boris Yeltsin and Bill Clinton reiterated yet again their pledges to push for further reductions of strategic nuclear weapons, but were unable to report any concrete steps toward the ratification of START II by the Russian Duma. According to a joint statement issued by the two leaders, “Russia and the United States will continue to fulfill their commitments of the ABM and START arms reduction agreements and cooperate for accelerated ratification of START II by Russia.” The two presidents also repeated their pledge, made at their Helsinki summit in March 1997 that after START II is ratified, talks will begin on START III.

The draft of the revised law on START II ratification prepared by the Duma was published on 9 December in the PIR Center Arms Control Letter. As expected, Article II of the law specifies a number of “extraordinary events,” which would “give the Russian Federation the right to withdraw from the [START II] Treaty.” These include violation of START II by the United States; a build-up of nuclear weapons by States not party to START II; “military deployment” decisions by the United States or NATO that “threaten the national security of the Russian Federation,” including the deployment of nuclear weapons in countries which have joined NATO since 1993; the deployment by any country of weapons that threaten the Russian early warning system; and “technical” or “economic” events that make it impossible for Russia to implement the Treaty or jeopardize its “environmental security.” The Duma’s version of the bill also includes a number of conditions that must be met before Russia would exchange instruments of ratification with the United States, the final step which would allow START II to enter into force. Among these are the ratification by the United States of the ABM Demarcation Agreements signed by the United States and Russia in September 1997. These agreements face opposition in the US Senate, which could refuse to ratify them, creating another potential obstacle to the implementation of START II.

In the wake of US and British air strikes against Iraq that began on 16 December 1998, Russian Presidential Representative to the State Duma Alexander Kotenkov expressed doubt that the current Duma would ratify START II. Kotenkov said on 17 December that “ratification is unlikely to take place until a new Duma has been elected.” The following Duma elections were scheduled for December 1999. The Duma reacted angrily to the US-led air strikes on Iraq, terming them “barbaric” and “an act of international terrorism” in a resolution adopted on 17 December by the vote of 394-1 with two abstentions.


Meeting with his U.S. counterpart Bill Clinton in Helsinki on 21 March, Russian President Boris Yeltsin pledged to push for speedy ratification of START II by the Russian Federal Assembly. In an attempt to accelerate ratification of the Treaty, Clinton and Yeltsin issued a joint statement on the “Parameters of Future Nuclear Reductions.” The statement was targeted at Russian parliamentary critics of START II. Under its terms, the deadline for dismantling the strategic delivery systems slated for elimination under START II would be extended from 2003 to 2007. This provision would allow Russia to spread out the cost of destroying its multiple-warhead land-based ICBMs, addressing the cost concerns of some Russian parliamentarians. Clinton and Yeltsin also outlined a proposed START III that would reduce both countries’ strategic arsenals to the level of 2,500-2,000 warheads by 2007.

This proposed treaty, with its lower warhead ceiling, would save Russia the expense of building several hundred new single-warhead land-based missiles to match US force levels under START II. However, the United States insisted that negotiations on START III could not begin until after START II has been ratified, although many Russian critics of START II have said that they would prefer to scrap the Treaty and immediately begin talks on START III. According to Clinton administration officials, the joint statement provides for “reciprocity,” since now the downloading of both US Minuteman III and Russian SS-19 ICBMs does not have to be completed until the end of 2007.

Meeting in New York, Russian Foreign Minister Yevgeniy Primakov and his US counterpart Madeleine Albright signed a Protocol to START II on 26 September, extending the deadline for destruction of weapons systems slated for elimination under the Treaty from 2003 to 2007. In addition to the Protocol, the two foreign ministers exchanged letters in which the United States and Russia pledged that pending their destruction; these systems would be “deactivated” by 2003. The letters specified that deactivation will be carried out by “removing the nuclear re-entry vehicles from the missiles, or by taking other jointly agreed steps.” The Russian letter contained a unilateral declaration that “the Russian Federation proceeds from the understanding that well in advance of the above deactivation deadline the START III treaty will be achieved and will enter into force,” a statement which the United States took note of in its letter.

The Protocol and letters formally codified the agreement reached by Presidents Clinton and Yeltsin at the Helsinki Summit in March 1997. The United States and Russia also released a joint agreed statement that enables the United States to download (remove) warheads from its Minuteman III ICBMs “at any time” before 31 December 1997. Under the terms of START I, Washington would previously have been required to download two warheads from its three-warhead Minuteman III missiles by 5 December 2001, effectively converting them into single-warhead ICBMs.



On 26 January, upon notification of the U.S. Senate’s ratification of START II (by an 84-7 vote), Russian President Yeltsin called U.S. President Bill Clinton pledging to push the Russian parliament to ratify the Treaty before the G-7 Moscow summit on nuclear safety in April. (The Russian constitution requires the Treaty’s ratification by both houses of parliament.)

On 17 October, U.S. Secretary of Defense William Perry addressed the State Duma Committees on Defense and International Affairs, arguing in favor of ratification of START II. According to Russian and Western reports, Perry was accorded a cool reception and his speech failed to impress the Duma. Shorter presentations by Senators Richard Lugar and Joseph Lieberman fared no better. Senator Lugar stressed that further funding for Cooperative Threat Reduction programs would not be forthcoming without START II ratification.


A Russian Duma internal report dated 26 October recommended modifying START II in order to allow Russia to continue deploying multiple-warhead ICBMs. The report also recommended that Russian START II ratification be conditioned upon completion of a US-Russian agreement on regional missile defenses. But Duma Defense Committee Chairman Sergei Yushenkov was quoted saying that “the Duma is unlikely to ratify the START II treaty in the near future, judging by the atmosphere of the deputies.”



On 28 September, Presidents Yeltsin and Clinton issued a joint statement that included their intention to seek early ratification of START II. Clinton and Yeltsin also stated that once START II was ratified, the United States and Russia were to deactivate the missiles slated for destruction under the Treaty by removing their warheads and removing them from alert status.


In the State of the Union address on 28 January, U.S. President George Bush proposed further strategic arms reduction to an unspecified limit (reportedly, to 4,700 warheads) under the condition of complete elimination of all MIRVed ICBMs. In the context of such an agreement, he promised to download the number of warheads on Minuteman ICBMs from three to one, to reduce the number of warheads on SLBMs by one-third compared to the START I projected SLBM force, and to convert “a substantial portion” of heavy bombers “to primarily conventional use.” He also announced a unilateral decision to terminate the B-2 program at 20 heavy bombers instead of the previously planned 75, cancelled the small ICBM program, ended production of new warheads for SLBMs, and terminated purchases of additional advanced cruise missiles.

The day following President Bush’s address, Russian President Yeltsin, in a special televised statement, suggested a warhead limit of 2,000-2,500 warheads, reportedly with the the de-MIRVing of both ICBMs and SLBMs. Yeltsin also declared that Russia had unilaterally terminated the production of its heavy bombers (Tu-160 and Tu-95MS), as well as long-range air-launched cruise missiles (ALCMs), and proposed renouncing the creation of new types of such missiles on a bilateral basis. He announced that Russia would no longer conduct exercises involving more than 30 heavy bombers, and had reduced by half the number of submarines with SLBMs on patrol. He proposed that Russia and the United States agree on detargeting their nuclear weapons.

On 17 June, Presidents Bush and Yeltsin signed the “joint understanding,” on which START II is based. This agreement committed Russia and the United States to a two-phase reduction of their strategic offensive arms to the level of 3,000 to 3,500 warheads each by the year 2003, or “if the United States can contribute to the financing of the destruction or elimination of strategic offensive arms in Russia,” by the year 2000. The agreement also called for elimination of all MIRVed ICBMs, a limit of 1,750 on the warheads of SLBMs, and a “real” account of warheads on heavy bombers (START I established an “average” number of warheads assigned to each heavy bomber, lower than the actual number of weapons deployed on each of them). The agreement also permitted the “reorientation” of heavy bombers from nuclear to conventional roles without additional conversion.



U.S. President George Bush proposed on 27 September to “use START I as a springboard to achieve additional stabilizing reductions.” In particular, he said that the United States would unilaterally terminate the program of development of the mobile MX Peacekeeper ICBM and proposed that the United States and the Soviet Union agree on the elimination of all MIRVed ICBMs.

On 5 October, responding to the initiatives proposed by U.S. President George Bush, Soviet President Mikhail Gorbachev stated that the deployment and modernization of MIRVed mobile ICBMs would be terminated and all rail-mobile ICBMs would remain in their permanent basing areas. The Soviet Union promised to unilaterally reduce its strategic nuclear weapons to 5,000 warheads instead of the 6,000 provided for under START I and proposed immediately, upon ratification of START I, to begin negotiations on reduction by half of the remaining strategic arsenals.


During a summit meeting in Washington in June, still in the middle of START I negotiations, U.S. President George Bush and Soviet President Mikhail Gorbachev signed a Joint Statement that outlined the two sides’ approach to the next START treaty. The statement expressed the intention to reduce strategic offensive arms “in a way consistent with enhancing strategic stability,” in particular through reduction of “concentration of warheads on strategic delivery vehicles” and increasing survivability of systems. They agreed that the agreement would include “measures related to the question of heavy missiles and MIRVed ICBMs.”

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Anti-Ballistic Missile (ABM) Treaty
The Anti-Ballistic Missile (ABM) Treaty, which was signed by the United States and the Soviet Union on May 26, 1972, and entered into force on October 3, 1972, constrained strategic missile defenses to a total of 200 launchers and interceptors per country, which were divided between two widely separated deployment areas. These restrictions were intended to prevent the establishment of a nationwide defense, and the creation of a base for deploying such a defense. The treaty was modified in 1974, reducing the permitted deployment areas to one per country. The United States withdrew from the ABM Treaty in 2002. For additional information, see the Anti-Ballistic Missile Treaty.
North Atlantic Treaty Organization (NATO)
The North Atlantic Treaty Organization is a military alliance that was formed in 1949 to help deter the Soviet Union from attacking Europe. The Alliance is based on the North Atlantic Treaty, which was signed in Washington on 4 April 1949. The treaty originally created an alliance of 10 European and two North American independent states, but today NATO has 28 members who have committed to maintaining and developing their defense capabilities, to consulting on issues of mutual security concern, and to the principle of collective self-defense. NATO is also engaged in out-of-area security operations, most notably in Afghanistan, where Alliance forces operate alongside other non-NATO countries as part of the International Security Assistance Force (ISAF). For additional information, see NATO.
Anti-Ballistic Missile (ABM) Treaty
The Anti-Ballistic Missile (ABM) Treaty, which was signed by the United States and the Soviet Union on May 26, 1972, and entered into force on October 3, 1972, constrained strategic missile defenses to a total of 200 launchers and interceptors per country, which were divided between two widely separated deployment areas. These restrictions were intended to prevent the establishment of a nationwide defense, and the creation of a base for deploying such a defense. The treaty was modified in 1974, reducing the permitted deployment areas to one per country. The United States withdrew from the ABM Treaty in 2002. For additional information, see the Anti-Ballistic Missile Treaty.


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