This annotated chronology is based on the data sources that follow each entry. Public sources often provide conflicting information on classified military programs. In some cases we are unable to resolve these discrepancies, in others we have deliberately refrained from doing so to highlight the potential influence of false or misleading information as it appeared over time. In many cases, we are unable to independently verify claims. Hence in reviewing this chronology, readers should take into account the credibility of the sources employed here.

Inclusion in this chronology does not necessarily indicate that a particular development is of direct or indirect proliferation significance. Some entries provide international or domestic context for technological development and national policymaking. Moreover, some entries may refer to developments with positive consequences for nonproliferation.

1960
France, now under the leadership of Charles De Gaulle, terminates nuclear assistance to Israel before the Dimona reactor is operational. After several months of negotiations, however, France agrees to proceed with construction on the conditions that Israel announces the project and pledges not to pursue a weapons program.
— Farr, Warner, The Third Temple's Holy of Holies: Israel's Nuclear Weapons, September 1999, <http://www.au.af.mil/au/awc/awcgate/awc-cps.htm>, Weissman, Steve and Krosney, Herbert, The Islamic Bomb: the Nuclear Threat to Israel and the Middle East, (New York, New York: Times Books, 1981), 113-114.

1960 to 1964
France may have helped Israel design and detonate its own nuclear device at the Reggan or Ekker proving grounds in Algeria.
— Pry, Peter, Israel's Nuclear Arsenal (Boulder, Colorado: Westview, 1984), 16.

1960 to 1965
The French government permits the nuclear company Saint-Gobain Nucleaire (SGN) to construct the Dimona reactor.
— Pry, Peter, Israel's Nuclear Arsenal (Boulder, Colorado: Westview, 1984), 12.

1960 to 1966
The United States provides Israel with 50 kilograms of uranium-235, of 90% purity, to fuel the reactor at Nachal Soreq. This amount of uranium of this purity could be used to manufacture several bombs.
— Pry, Peter, Israel's Nuclear Arsenal (Boulder, Colorado: Westview, 1984), 8.

13 February 1960
France tests its first nuclear device. It is believed that collaboration between French and Israeli scientists is so extensive that the test represents the creation of two nuclear powers. Israeli observers are reported to be granted "unrestricted access to French nuclear test explosion data."
—"Post-Mortem on SNE [Special National Intelligence Estimate] 100-8-60; Implications of the Acquisition by Israel of a Nuclear Weapons Capability," Draft, 31 January 1961, Department of State Lot files, Lot No. 57D688, USNA as cited in Cohen, Avner, Israel and the Bomb (New York: Colombia University Press, 1998), 82-83; Weissman, Steve and Krosney, Herbert, The Islamic Bomb: the Nuclear Threat to Israel and the Middle East, (New York, New York: Times Books, 1981), 114-117

16 June 1960
The reactor at Nachal Soreq is activated under safeguards to prevent it from producing weapons-usable material.
— Pry, Peter, Israel's Nuclear Arsenal (Boulder, Colorado: Westview, 1984), 7.

Mid 1960
The Central Intelligence Agency tells President Eisenhower that what is being constructed in the Negev Desert at Dimona is a large nuclear reactor with the potential for producing fissionable material in quantities sufficient to produce nuclear weapons—about 1.2 per year.
— Green, Stephen, Taking Sides, America's Secret Relations with a Militant Israel, (New York: William and Morrow Company, 1984), 153.

2 December 1960
Before Israel can voluntarily disclose its nuclear program, the U.S. State Department issues a statement revealing Israel's secret nuclear installation.
—Cohen, Avner, "Most Favored Nation," The Bulletin of American Scientists, 51, No. 1 (January-February 1995): 44-53.

8 December 1960
The U.S. Central Intelligence Agency issues a report outlining Dimona's implications for nuclear proliferation.
—Cordesman, Anthony, Weapons of Mass Destruction in the Middle East, Center for Strategic and International Studies, 15 April 2003.

16 December 1960
Precipitated by a Time magazine article alleging that a "small power... neither of the communist nor the NATO bloc" was developing a nuclear weapons capability, the London Daily Express names Israel as the state, adding that "British and American intelligence authorities believe that the Israelis are well on their way to building their first nuclear bomb." Two days later AEC Chairman Jon McCone appears on the television program "Meet the Press" to confirm that Israel is building a nuclear reactor and that the United Sates has inquired with the Israeli government about it. The following day's New York Times also runs a similar exposé on the Israel's secret nuclear program.
—Cohen, Avner, Israel and the Bomb (New York: Colombia University Press, 1998), 88-9.

21 December 1960
In the Prime Minister's only public statement about the Dimona reactor, David Ben Gurion tells the Knesset that no bombs are being built and that the complex "is designed exclusively for peaceful purposes."
— Green, Stephen, Taking Sides, America's Secret Relations with a Militant Israel, (New York: William and Morrow Company, 1984), 154, Cohen, Avner, Israel and the Bomb (New York: Colombia University Press, 1998), 91.

January 1961
Israeli Prime Minister David Ben Gurion informs the Knesset that the Dimona complex is not in fact a textile plant or a pumping station (as he had previously stated to foreign leaders), but a "scientific institute for research in problems of arid zones and desert flora and fauna."
— Green, Stephen, Taking Sides, America's Secret Relations with a Militant Israel, (New York: William and Morrow Company, 1984), 159.

20 May 1961
As part of a diplomatic nonproliferation offensive launched by President Kennedy, two AEC scientists visit the Dimona reactor in the Negev desert. The visit, set up by Kennedy and Ben Gurion, is the first by American scientists to the reactor complex.
—Cohen, Avner, Israel and the Bomb (New York: Colombia University Press, 1998), 105.

30 May 1961
President Kennedy and Ben Gurion meet at the Waldorf Astoria Hotel in New York to discuss Dimona.
—Cohen, Avner, Israel and the Bomb (New York: Colombia University Press, 1998), 105.

1962
Communist and Mapam Knesset members propose a resolution advocating the establishment of a nuclear weapons free zone covering Israel and the Arab states. Prime Minister Ben Gurion responds by recalling that his government backed the Basic Principles approved by the Knesset in 1959 that advocate total regional disarmament, including the abolition of all armed forces, "on condition that constant and unhampered mutual control of this agreement is assured and that the borders and sovereignty of these States are not affected."
— Green, Stephen, Taking Sides, America's Secret Relations with a Militant Israel, (New York: William and Morrow Company, 1984), 156.

1962
The Dimona reactor, officially know as the Negev Nuclear Research Center, goes critical.
— Farr, Warner, The Third Temple's Holy of Holies: Israel's Nuclear Weapons, September 1999, <http://www.au.af.mil/au/awc/awcgate/awc-cps.htm>.

1962 to 1969
In response to U.S. pressure, Israel commits to use its nuclear facility for only peaceful purposes and allows American teams to inspect the facility twice a year. The inspection teams, however, do not see much of the facility, especially the underground portions hidden by Israeli agents.
—Hersh, Seymour, The Sampson Option (New York: Random House, 1991), 196.

26 September 1962
The second visit by American scientists to the Dimona complex takes place.
—Cohen, Avner, Israel and the Bomb (New York: Colombia University Press, 1998), 112.

October 1962
Israeli Foreign Minster Golda Meir addresses the United Nations General Assembly on the subject of Israel's attitude toward nuclear weapons, stating that "Israel watches with special concern the growing nuclear arming and it is our declared policy to support every effort to remove the awful dangers to humanity arising out of the continuation of this process. Israel therefore supports every means that may limit and decrease weapons in the world."
— Green, Stephen, Taking Sides, America's Secret Relations with a Militant Israel, (New York: William and Morrow Company, 1984), 163.

January 1963
Israeli Deputy Defense Minister Shimon Peres declares that the Dimona complex is to play part in the Defense Ministry's plan to desalinate a billion cubic meters of seawater annually for the irrigation of the Negev Desert. Aharon Wiener, director of the Israel Water Company Tahal, calls this statement "unfounded."
— Green, Stephen, Taking Sides, America's Secret Relations with a Militant Israel, (New York: William and Morrow Company, 1984), 163.

2 April 1963
In an informal meeting with President Kennedy at the White House, Shimon Peres states that Israel "will not introduce nuclear weapons to the region, and certainly will not be the first," laying the groundwork for what is to become Israel's doctrine of nuclear opacity for years to come.
—Cohen, Avner, Israel and the Bomb (New York: Colombia University Press, 1998), 119.

17 April 1963
Egypt, Syria, and Iraq sign in Cairo an Arab Federation Proclamation calling for a military union to bring about the liberation of Palestine. The proclamation is a step towards the realization of Israeli Prime Minister David Ben Gurion's greatest fear—a Pan-Arab military alliance bent on Israel's destruction.
—Cohen, Avner, Israel and the Bomb (New York: Colombia University Press, 1998), 119-23.

5 August 1963
Israel signs the Partial Test Ban Treaty in Moscow.
— Green, Stephen, Taking Sides, America's Secret Relations with a Militant Israel, (New York: William and Morrow Company, 1984), 165, Cohen, Avner, Israel and the Bomb (New York: Colombia University Press, 1998), 161.

December 1963
The Dimona reactor goes into operation.
— Pry, Peter, Israel's Nuclear Arsenal (Boulder, Colorado: Westview, 1984), 12.

1964
Israeli military officials participate in testing of French nuclear devices in the Saharan Desert.
— Green, Stephen, Taking Sides, America's Secret Relations with a Militant Israel, (New York: William and Morrow Company, 1984), 167.

1964 or 1965
The French complete work on an underground plutonium reprocessing plant at the Dimona complex.
— Farr, Warner, The Third Temple's Holy of Holies: Israel's Nuclear Weapons, September 1999, <http://www.au.af.mil/au/awc/awcgate/awc-cps.htm>.

17 to 18 January 1964
American scientists visit the Dimona complex and learn that the reactor went critical on 26 December 1963. The visit, totally controlled by the Israeli official hosts, is the continuation of a secret arrangement set up by President Kennedy and Prime Minister Ben Gurion. The American team visits at times and places of the Israeli government's choosing.
— Green, Stephen, Taking Sides, America's Secret Relations with a Militant Israel, (New York: William and Morrow Company, 1984), 166, Cohen, Avner, Israel and the Bomb (New York: Colombia University Press, 1998), 179.

1965
East German President Walter Ulbricht alleges that Israel and West Germany have concluded "joint preparations to produce atomic weapons," but offers no proof of his allegations.
— Pry, Peter, Israel's Nuclear Arsenal (Boulder, Colorado: Westview, 1984), 35.

1965
The Egyptian Air Force claims to posses aerial reconnaissance intelligence obtained in overflights of the Negev desert identifying the Dimona complex as a nuclear reactor. Half of the 50 HAWK antiaircraft missiles provided to Israel by the U.S. are reportedly positioned around the Dimona complex.
— Norden, Lon O., Nicole, David, Phoenix over the Nile (Washington, D.C.: Smithsonian Institute Press, 1996), 192-193, O'Balance, Edgar, The Third Arab-Israeli War (London: Faber and Faber, 1972), 54.

1965
The U.S. government accuses Zalman Shapiro, president of the Nuclear Materials and Equipment Corporation (NUMEC) in Apollo, Pennsylvania, of "losing" 200 pounds of highly enriched uranium. Investigations by the Federal Bureau of Investigation, Central Intelligence Agency, and the Atomic Energy Commission are inconclusive. Some allege that the misplaced uranium eventually found its way to the Israeli nuclear program. The decommissioning of NUMEC in the early 1980's, however, casts doubt on such allegations when over 100 kilograms of unaccounted for uranium are discovered throughout the facility.
— Interview with a senior technical official of the Nuclear Regulatory Commission as cited in Hersh, Seymour, The Sampson Option (New York: Random House, 1991), 257, Green, Stephen, Taking Sides, America's Secret Relations with a Militant Israel, (New York: William and Morrow Company, 1984), 169-179.

28 January 1965
American scientists visit Dimona.
—Cohen, Avner, Israel and the Bomb (New York: Colombia University Press, 1998), 181.

10 March 1965
After failing to persuade Israeli officials to accept IAEA safeguards on the Dimona reactor, White House aide Robert Komer compromises with Levi Eshkol, the result of which is a "Memorandum of Understanding" between the two states. The document expresses the United States' "concern for the maintenance of Israel's security" and renews its commitment to the "independence and integrity of Israel." Israel in turn reaffirms its pledge that it "will not be the first to introduce nuclear weapons into the Arab-Israel area." The document further solidifies Israel doctrine of nuclear opacity.
—Cohen, Avner, Israel and the Bomb (New York: Colombia University Press, 1998), 205-7.

1966
Israel is capable of producing weapons-grade fissile material, weapons design, and the testing of deliver means. According to French CEA official Pierre Pean, "the first plutonium extraction tests took place during the second half of 1965," and by 1966 Israel had enough plutonium to "manufacture the bomb during 1966, or at the latest early 1967."
—Cohen, Avner, Israel and the Bomb (New York: Colombia University Press, 1998), 231.

2 April 1966
American scientists visit Dimona. The visit is disclosed in the New York Times three months later, embarrassing Israeli President Levi Eshkol.
—Cohen, Avner, Israel and the Bomb (New York: Colombia University Press, 1998), 186.

May 1966
Prime Minister Levi Eshkol fires long-time proponent of the nuclear program Ernst Bergman from his position as Chairman of the Israel Atomic Energy Commission. The IAEC is reformed and transferred out of the Ministry of Defense to the Prime Minister's office. Eshkol assumes chairmanship of the IAEC and new commission members are appointed whose background relate primarily to the civilian uses of nuclear energy.
— Green, Stephen, Taking Sides, America's Secret Relations with a Militant Israel, (New York: William and Morrow Company, 1984), 175, Pry, Peter, Israel's Nuclear Arsenal (Boulder, Colorado: Westview, 1984), 19.

18 May 1966
Prime Minister Levi Eshkol tells the Knesset that Israel will not be the first to introduce nuclear weapons into the region. He also states that Israel does not possess nuclear weapons. He tells the Knesset that his government reserves the right to continue research and training at Dimona, but that the atomic bomb development program has been terminated.
— Green, Stephen, Taking Sides, America's Secret Relations with a Militant Israel, (New York: William and Morrow Company, 1984), 17-6.

October 1966
According to some Western sources, Israel conducts an underground nuclear test at Al-Naqab in the Negev desert.
— Nashif, Taysir N., Nuclear Weapons and the Middle East: Dimensions and Responsibilities (Princeton, New Jersey: Kingston Press, 1984), 22-244.

November 1966
An accident occurs at the Dimona complex, the cleanup of which lasts until February 1967.
—Cohen, Avner, Israel and the Bomb (New York: Colombia University Press, 1998), 186.

2 November 1966
Israel is suspected of performing some type of non-nuclear test as part of its continued pursuit of nuclear capability. It is assumed to have been a zero-yield or implosion test in the Negev desert.
—Cordesman, Anthony, Weapons of Mass Destruction in the Middle East, Center for Strategic and International Studies, 15 April 2003, Farr, Warner, The Third Temple's Holy of Holies: Israel's Nuclear Weapons, September 1999, <http://www.au.af.mil/au/awc/awcgate/awc-cps.htm>.

1967
An Israeli-Brazilian nuclear agreement concludes.
— Pry, Peter, Israel's Nuclear Arsenal (Boulder, Colorado: Westview, 1984), 24.

1967
France discontinues uranium supplies to Israel collected from the former French colonies Gabon, Niger, and the Central African Republic.
— Cordesman, Anthony, Perilous Prospects: The Peace Process and the Arab-Israeli Military Balance (Boulder, Colorado: Westview Press, 1996), 120.

1967
An anonymous French source alleges that Israel sends France 40 tons of Dimona's spent fuel, rich with plutonium, and the French technicians separate and return "about half" or at least enough for "fifteen to twenty bombs."
— Pry, Peter, Israel's Nuclear Arsenal (Boulder, Colorado: Westview, 1984), 15.

22 April 1967
American scientists visit Dimona, again finding no evidence of weapon-related activities.
—Cohen, Avner, Israel and the Bomb (New York: Colombia University Press, 1998), 186.

May 1967
Israel assembles two nuclear bombs ten days before the outbreak of the Six Day War.
—Interview with former Israeli government official as cited in Hersh, Seymour M., The Sampson Option (New York: Random House, 1991), 225 and 236-237 as cited in Burrows, William E. and Winderm, Robert, Critical Mass. The Dangerous Race for Superweapons in a Fragmenting World (New York, New York: Simon and Schuster, 1994), 279-280.

May 1967
Israeli Defense Ministerial Committee member Yigal Allon amends his 1959 list of situations that would justify Israel in launching a preemptive war to include "an aerial attack on nuclear reactors and scientific institutions."
—Cohen, Avner, Israel and the Bomb (New York: Colombia University Press, 1998), 270.

17 May 1967
Egyptian aircraft make high-altitude reconnaissance flights over Dimona. The reactors at Nachal Soreq and Dimona become high-priority targets for Egypt in the Six Day War.
—Cohen, Avner, Israel and the Bomb (New York: Colombia University Press, 1998), 259, 266, 269.

Pre-June 1967
Israel considers overflights by Egyptian Air Force planes possible reconnaissance for an impending military strike. Such overflights, along with the withdrawal of United Nations peacekeeping forces and the repositioning of Egyptian troops to the Sinai, are reportedly triggers to a possible Israeli preemptive strike.
— Brecher, Michael, Decision in Crisis. Israel, 1967 and 1973 (Berkeley, California: University of California Press, 1980), 104, 230-231.

June 1967
During the Six-Day War, Israel mistakenly shoots down one of its own Mirage jetfighters for flying too close to the Dimona reactor facility. Israeli Prime Minister Levi Eshkol orders that both of the two Israeli nuclear warheads be armed during what becomes the country's first nuclear alert.
—Interview with Israeli scientist quoting the Hebrew-language memoirs of General Israel Lior as cited in Burrows, William E. and Winderm, Robert, Critical Mass. The Dangerous Race for Superweapons in a Fragmenting World (New York, New York: Simon and Schuster, 1994), 280.

14 June 1967
A New York Times article alleges that authoritative sources in Tel Aviv report "that Israel's next move may be to make the atom bomb."
—"Israel Said to Plan to Make Atom Bomb," New York Times, 14 June 1967.

1968
Having lost its uranium supply from France, Israel is suspected to have executed Operation Plumbat, a clandestine action carried out by the Mossad. Using a West German front company, Israeli operatives secure 200 tons of uranium oxide in Antwerp. Mossad agents conduct a high seas, ship-to-ship transfer of the 560 barrels of uranium to another vessel in the Mediterranean. The secret cargo is then transported to Israel. The drums containing uranium are labeled "plumbat," meaning lead.
—Pringle, Peter, The Nuclear Barons (New York: Holt, Rinehart, and Winston, 1981), 297; Davenport, Elaine, Eddy, Paul, and Gillman, Peter, The Blumbat Affair (London: Andre Deutsch, 1978) as cited in James, Raviv, Dan and Melman, Yossi, Every Spy a Prince: the Complete History of Israel's Intelligence Community, (Boston, Massachusetts: Houghton Mifflin Company, 1990), 198-199; Weissman, Steve and Krosney, Herbert, The Islamic Bomb: the Nuclear Threat to Israel and the Middle East, (New York, New York: Times Books, 1981), 124-128. See also Ha'aretz, 26 June 1978.

Early 1968
The U.S. Central Intelligence Agency reports that Israel has successfully produced four nuclear weapons. This assumption is based on conversations between Carl Duckett, head of the CIA's Office of Science and Technology, and Edward Teller, father of the hydrogen bomb. Teller said that, based on conversations with friends in the Israeli scientific and defense establishment, he concluded that Israel was capable of building a nuclear weapon. Teller also asserted that Israel would not publicly test a nuclear device.
—Cordesman, Anthony, Weapons of Mass Destruction in the Middle East, Center for Strategic and International Studies, 15 April 2003.

Early 1968
An intense debate among leading Israeli security policymakers ensues. Nuclear weapons opponents Prime Minister Levi Eshkol, Mapai leader Golda Meir, and Cabinet Defense Committee member Yigal Allon veto the proposed construction of a plutonium separation plant. Shortly afterwards Eshkol discovers that Defense Minister Moshe Dyan has secretly ordered the start of construction on a separation plant. Eshkol and his advisers fail to stop construction already underway and approve the Defense Ministry's project.
—"How Israel Got the Bomb," Time Magazine, 12 April 1976.

1968 and 1969
In his book Israel's Nuclear Arsenal, Peter Pry alleges that Israeli agents in Britain and France make teargas attacks against government trucks carrying uranium in order to secure fuel for the Dimona reactor and nuclear weapons program.
— Pry, Peter, Israel's Nuclear Arsenal (Boulder, Colorado: Westview, 1984), 29.

1969
Ernst David Begrmann states in an interview that as early as 1949 or 1950 it was thought "at the highest political level" that France would be the logical source for nuclear assistance to Israel.
—Cohen, Avner, Israel and the Bomb (New York: Colombia University Press, 1998), 25.

12 July 1969
American scientists visit the Dimona nuclear complex for the last time and the visitation program set up under President Kennedy and Levi Eshkol in 1963 is discontinued in 1970. The inspection team complains in writing that because the Israelis hurried and limited their earlier inspections and did not permit them to move about freely, they cannot guarantee that no weapons-related work is being done at Dimona.
— Pry, Peter, Israel's Nuclear Arsenal (Boulder, Colorado: Westview, 1984), 15, Cohen, Avner, Israel and the Bomb (New York: Colombia University Press, 1998), 323.

5 September 1969
The U.S. delivers F-4E Phantom jets, equipped with hardware enabling nuclear weapons delivery, to Israel. The State Department's objections to the delivery are overruled by the Whitehouse, which denies the allegations that the delivery took place.
—"U.S. Will Start Delivering F-4 Jets to Israel in 1969," New York Times, 28 December 1968 as cited in Green, Stephen, Living by the Sword: America and Israel in the Middle East, 1968-1987 (London: Faber, 1988), 18-19, Spector, Leonard S., "Foreign-Supplied Combat Aircraft: Will They Drop the Third World Bomb?" Journal of International Affairs 40, no. 1 (1986): 145 (n.5).

Late 1960s
The United States proposes to give Israel technical assistance and $40 million for construction of a nuclear desalinization plant if Israel agrees to international safeguards on the Dimona complex. Israel refuses.
— Pry, Peter, Israel's Nuclear Arsenal (Boulder, Colorado: Westview, 1984), 15.

	Updated September 2005