India Nuclear Overview

This page is part of the India Country Profile.

• Click for Recent Developments and Current Status

India possesses both nuclear weapons and extensive nuclear fuel cycle capabilities. India tested its first nuclear device in May 1974, and remains outside both the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) and the Comprehensive Nuclear Test Ban Treaty (CTBT). However, India has a facility-specific safeguards agreement in place with the International Atomic Energy Agency (IAEA) and a waiver from the Nuclear Suppliers Group (NSG) allowing it to participate in global civilian nuclear technology commerce. India has a sizable and growing nuclear arsenal, primarily due to decades of conflict with its nuclear-armed neighbor Pakistan.

According to the 2019 SIPRI Yearbook, the Indian arsenal includes 130 to 140 warheads. ¹ The ranges of such estimates are generally dependent on analyses of India’s stockpile of weapons-grade plutonium, which is estimated at 0.58 ± 0.15 tons. ² India has also stockpiled roughly 4.0 ± 1.4 tons of highly enriched uranium (HEU), some of which is intended for use in nuclear submarines and research reactors. ³

The plutonium for India’s nuclear arsenal is obtained from the 100 MWt research reactor, Dhruva, which began operations in 1988. ⁴ Another 40 MWt CIRUS reactor produced about 4 to 7 kg of weapons-grade plutonium annually until it was decommissioned in 2010 under the separation plan of the U.S.-India nuclear cooperation agreement. ⁵ Irradiated fuel from the reactors is reprocessed at the Plutonium Reprocessing Plant in Trombay, which has a capacity of roughly 50 tons of spent nuclear fuel per year. ⁶ A 500MW prototype fast breeder reactor (PFBR) at Kalpakkam in the South Indian state of Tamil Nadu was expected to reach criticality by 2019 to increase India’s plutonium production capacity, but has not yet reached this goal. Starting in 2021, India plans to construct six more PFBR-type reactors. ^{7 8}

Assessments of the yield and reliability of India’s nuclear devices vary considerably. When India tested its first fission device in May 1974, Indian scientists claimed the device had a yield of about 12 kilotons (kt), while other independent analysts estimated a much lower yield. ⁹ Similar disputes surrounded India’s May 1998 tests. After its first of round of tests on 11 May, India announced that it had simultaneously tested three nuclear devices: a thermonuclear device, a fission device, and a sub-kiloton device with a combined yield of around 65 kt. ¹⁰ However, analysts and scientists outside of India – citing evidence from geologic and seismic data – concluded that the cumulative yield of the Indian tests was lower. ^{11 12} Some scientists in India seem to agree with this analysis and argue that India should therefore refrain from signing the Comprehensive Nuclear Test Ban Treaty (CTBT) and conduct further tests. ^{13 14 15} However, former leaders of the Atomic Energy Commission of India who oversaw these tests dispute such claims, maintaining that their original estimates were correct and that further testing is unnecessary. ^{16 17 18}

1947 to 1974: Developing a Peaceful Nuclear Program

India’s nuclear program was mainly conceived by Homi Bhabha, an influential scientist who persuaded political leaders to invest resources in the nuclear sector. ¹⁹ The first Indian Prime Minister, Jawaharlal Nehru, launched an ambitious nuclear program to boost the country’s prestige and self-reliance in energy with primary focus on producing inexpensive electricity. However, the decision to develop the complete nuclear fuel cycle also gave India the technical capability to pursue nuclear weapons. ²⁰

In the years that followed, the internal debate over whether India should develop a nuclear explosive device continued. On one hand, the scientific establishment wanted to prove that it was technically capable of detonating a nuclear device, whereas hawks within the security establishment pointed to security developments in China and elsewhere as necessitating a nuclear deterrent. ²¹ Many politicians opposed nuclear weapons both for economic and moral reasons, arguing that nuclear weapons would not make India safer, and that the solution to nuclear proliferation was comprehensive global nuclear disarmament. ²² As a result, a consensus emerged on both sides that India should not sign the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) when it was opened for signature in 1968 unless the nuclear weapon states agreed to a clear plan for nuclear disarmament. ²³

Prime Minister Lal Bahadur Shastri authorized theoretical work on the Subterranean Nuclear Explosion for Peaceful Purposes (SNEPP) project in November 1964. ²⁴ In the late 1960s nuclear scientists continued to develop the technical capacity for a nuclear explosion, although the political decision had not yet been made to carry out the test. ²⁵ Ultimately, on 18 May 1974, under orders from Prime Minister Indira Gandhi, India tested a fission device which it described as a “peaceful nuclear explosion” (PNE). ²⁶

1974 to 1998: The Slow Path Toward Weaponization

India’s 1974 nuclear test was condemned by many countries as a violation of the peaceful-use agreements underlying U.S. and Canadian-supplied nuclear technology and material transfers, and was a major contributing factor to the formation of the Nuclear Suppliers Group (NSG). ²⁷ However, due to international alarm about the military implications of its nuclear explosion, India did not follow the 1974 test with subsequent tests, nor did it immediately weaponize the device design that it had tested. ²⁸ Prime Minister Rajiv Gandhi authorized weaponization of India’s nuclear capability in late 1980s as a response to oblique nuclear threats issued by Pakistan in the wake of the 1986 to 1987 Brasstacks crisis. ^29 30 At the same time, India continued to support efforts for nuclear disarmament. In 1988, Prime Minister Rajiv Gandhi submitted an Action Plan for a Nuclear-Weapons-Free and Non-Violent World Order to the United Nations General Assembly. ³¹

As negotiations on the CTBT rapidly progressed in the early 1990s, India came to regard the CTBT as an instrument of nonproliferation that sought to freeze countries’ nuclear capabilities. This, along with the indefinite extension of the NPT, reignited domestic political pressure to conduct further tests. ³² In 1995, the Narasimha Rao government considered an accelerated program of nuclear tests but test preparations were detected by U.S. intelligence agencies, and the resultant U.S. diplomatic pressure convinced the Rao government to postpone the tests. ³³ When Prime Minister Atal Bihari Vajpayee came to power in 1998, his government authorized two rounds of nuclear tests on 11 and 13 May 1998, after which India formally declared itself to be a nuclear-weapon state. ³⁴ Almost no one outside of India foresaw the test; however, geospatial analysis by Vipin Gupta and Frank Pabian had identified a likely site and timeframe for the test. ³⁵

1998 to 2009: India as an Emerging Nuclear Power

India’s nuclear tests were followed within a month by a similar set of tests by Pakistan, resulting in fears in the international community of an arms race or an escalation of conflict between the two openly declared nuclear powers in South Asia. ³⁶ The 1999 Kargil War and the 2001 to 2002 Twin Peaks Crisis heightened tensions between the two countries, although these conventional conflicts did not escalate to the nuclear level. ^{37 38} The US government imposed sanctions on both India and Pakistan in response to their 1998 nuclear tests. ³⁹

After the 1998 tests the Indian government established a National Security Advisory Board, which issued a Draft Report on Indian Nuclear Doctrine in 1999 that broadly outlined India’s nuclear no-first-use policy and defensive posture of “credible minimum nuclear deterrence.” ⁴⁰ In January 2003, a Ministry of External Affairs press release maintained adherence to no-first-use, although with the condition that nuclear weapons could also be used in retaliation for a biological or chemical attack, or to protect Indian forces operating in Pakistan. ⁴¹ In line with this posture, India does not keep its nuclear force at a heightened state of alert. The country’s nuclear weapons remain under the control of the civilian Nuclear Command Authority (NCA), comprising of a Political Council, chaired by the Prime Minister, and an Executive Council, led by the National Security Advisor. ⁴²

A turning point in U.S.-India relations occurred when plans for negotiating a U.S.-India nuclear cooperation agreement were unveiled in July 2005 under the George W. Bush administration. This agreement, and the subsequent endorsement of India’s case by the Nuclear Suppliers Group (NSG), enabled India to engage in international nuclear trade. In return, India agreed to allow safeguards on a select number of its nuclear facilities that are classified as “civilian” in purpose. The remaining “military” facilities remained off-limits to international inspectors. The U.S. Congress passed the Hyde Act in January 2006 to exempt nuclear cooperation with India from provisions of the U.S. Atomic Energy Act, allowing for the adoption of a bilateral 123 nuclear cooperation agreement in August 2007. ⁴³ In September 2008, the NSG approved an exemption allowing the members of this export control regime to conduct nuclear trade with India. ⁴⁴ Finally, a safeguards agreement for select civilian nuclear facilities was concluded between India and the International Atomic Energy Agency (IAEA) in February 2009, after approval by the IAEA Board of Governors the previous year. ⁴⁵

2009 to Present: India as an Established Nuclear Power

In October 2009, India submitted a separation plan to put its civilian nuclear facilities under IAEA safeguards by 2014. ⁴⁶ In late July 2010, India and the United States signed a bilateral agreement allowing India to reprocess U.S.-obligated nuclear material at two new reprocessing facilities, to be constructed and placed under IAEA safeguards. ⁴⁷ However, the nuclear power industry did not grow as expected because India’s liability laws regulating civilian nuclear power plants far exceeded the international standards for nuclear liability and held suppliers legally liable for any damages resulting from accidents. To address these concerns and give impetus to nuclear power industry, India ratified the IAEA Convention on Supplementary Compensation for Nuclear Damage in 2016. ⁴⁸

By 2019, India had put total of 26 reactors under IAEA safeguards. ⁴⁹ Enabled by the NSG waiver granted to it in 2008, India has signed nuclear cooperation agreements with Russia, United States, France, United Kingdom, South Korea, Canada, Argentina, Kazakhstan, Mongolia, Australia, Sri Lanka, Japan, Vietnam, Bangladesh, Czech Republic and Namibia. ⁵⁰ Additionally, India continues to participate in international nuclear trade and has signed agreements with Canada, Kazakhstan and Australia to supply uranium to fuel its civilian nuclear reactors. Negotiations are currently underway for concluding negotiations to construct six reactors in the Indian state of Andhra Pradesh by Westinghouse. ⁵¹

India was recently accepted as a member of three of the four major export control regimes. It was admitted as a member into the Missile Technology Control Regime (MTCR) in 2016, Wassenaar Arrangement in 2017 and Australia Group in 2018. ^{52 53 54}

India has been actively pursuing membership into the NSG and has received explicit support for its membership from many current NSG members including the United States, Russia, Switzerland and Japan. ^{55 56 57 58} In arguing for NSG membership, India has portrayed itself as a responsible nuclear power, pointing to its positive record on nonproliferation and consistent support for complete nuclear disarmament. ⁵⁹ However, China does not support an explicit membership in the NSG for India but instead proposes a two-step approach: first would be to reach consensus on a non-discriminatory resolution that would apply to all non-NPT countries alike and then discuss individual membership applications by non-NPT countries. ⁶⁰ India argues that its membership should be considered under current rules because NSG is an export-control mechanism and not a nonproliferation one so question of linking NSG membership to the NPT membership does not arise. ⁶¹ Furthermore, India argues that there is a precedent for non-signatories of NPT joining the NSG when France became a founding member of the NSG in 1974 but did not accede to the NPT until 1992. ⁶²

India’s declared nuclear posture is of credible minimum deterrence and has successfully developed a strategic triad of nuclear delivery systems. ^{63 64} India has not signed the CTBT, but maintains a unilateral moratorium on nuclear testing and supports negotiations for a Fissile Material Cut-off Treaty (FMCT) that is “universal, non-discriminatory, and internationally verifiable.” ⁶⁵ The Indian mission to the United Nations has also submitted several draft recommendations on “reducing nuclear danger,” which include “steps to reduce the risks of unintentional and accidental use of nuclear weapons, including through de-alerting and de-targeting nuclear weapons.” ⁶⁶ At the same time, India has remained firmly outside of the NPT, arguing that “nuclear weapons are an integral part of our national security and will remain so pending the global elimination of all nuclear weapons.” ⁶⁷ India maintains its official commitment to no-first-use of nuclear weapons. However, during prepared remarks at the Pokhran nuclear test site in August 2019, Indian Defence Minister Rajnath Singh implied that India’s no first use policy would not be continued indefinitely. ⁶⁸