Pakistan is one of nine states that possess nuclear weapons. Pakistan is not party to the Nuclear Non-Proliferation Treaty. Pakistan's arsenal is estimated at 170 nuclear weapons as of 2025. Pakistan carried out two nuclear tests, Chagai-I and Chagai-II, both in 1998 and underground.
Pakistan's nuclear weapons programme began in 1972 under Prime Minister Zulfikar Ali Bhutto following Pakistan's defeat in the Indo-Pakistani War of 1971 and India's advancing nuclear programme. The programme was developed through a combination of domestic scientific research, clandestine procurement networks associated with Abdul Qadeer Khan, as well as external political and financial support.
During its early development, the government sought political and financial backing from several Muslim-majority countries and Arab states in the MENA region. Scholars identify Saudi Arabia as providing prolonged financial assistance that helped sustain the programme during periods of economic pressure and international sanctions, while Libya under then dictator Muammar Qaddafi is described as having provided both financial and material support during the programme's formative period.
Pakistan's nuclear weapons doctrine, full spectrum deterrence, officially rejects no first use, promising to use "any weapon in its arsenal" to protect its national interests in the event of an attack. Pakistan's primary strategic concern is potential conflict with India, which also possesses nuclear weapons.
Pakistan operates approximately 126 land-based missiles, primarily ballistic, of various short, medium, and intermediate ranges. Approximately 36 bombs and Ra'ad I/Ra'ad-II cruise missiles are assigned to Mirage III and Mirage 5 fighter aircraft. The Babur-III submarine-launched cruise missile is under development. Pakistan may possess smaller boosted fission weapons, but is not believed to have tested thermonuclear weapons.
Since 2001, US officials have prioritised safeguarding Pakistan's nuclear arsenal from potential nuclear terrorism, supplying equipment and training, and drafting military contingency plans.
Pakistan is not widely suspected of either producing biological weapons or having an offensive biological programme. Pakistan is a party to the Geneva Protocol, Chemical Weapons Convention, as well as the Biological Weapons Convention.
History After the Partition of India in 1947, India and Pakistan have been in conflict over several issues, including the disputed territory of Jammu and Kashmir. Multiple wars and conflicts, especially the 1971 Indo-Pakistan War and the subsequent Indian nuclear tests motivated Pakistan to become a nuclear power as part of its defence and energy strategies. Pakistan's subsequent pursuit of nuclear weapons was supported not only by domestic scientific development but also by financial assistance from several allied states during the early stages of the programme, including Libya and Saudi Arabia.
Initial non-weapon policy (Pre-1971)
In 1953, Foreign Minister Muhammad Zafarullah Khan publicly stated that "Pakistan does not have a policy towards the atom bombs". Following the announcement, on 11 August 1955, the United States and Pakistan reached an understanding concerning the peaceful and industrial use of nuclear energy which also included a pool-type reactor worth $350,000. Pakistan's nuclear energy programme was established and started in 1956, following the establishment of Pakistan Atomic Energy Commission (PAEC). Pakistan became a participant in US President Eisenhower's Atoms for Peace programme. Although proposals to develop nuclear weapons were made in the 1960s by several officials and senior scientists, Pakistan followed a strict non-nuclear weapon policy from 1956 until 1971, as PAEC under its chairman Ishrat Hussain Usmani made no efforts to acquire nuclear fuel cycle technology for the purposes of an active nuclear weapons programme. The first thing that was to be undertaken was the search for uranium, which continued from 1960 to 1963. Uranium deposits were discovered, and the first-ever national award was given to the PAEC. Mining of uranium began in the same year. Dr. Abdus Salam and Dr. Ishrat Hussain Usmani also sent a large number of scientists to pursue doctorate degrees in the field of nuclear technology and nuclear reactor technology. The next landmark under Abdus Salam was the establishment of PINSTECH – Pakistan Institute of Nuclear Science and Technology, at Nilore near Islamabad. The principal facility there was a 5MW research reactor, commissioned in 1965 and consisting of the PARR-I, which was upgraded to 10 MWe by Nuclear Engineering Division under Munir Ahmad Khan in 1990. The PARR-I reactor was, under the agreement signed by PAEC and ANL, provided by the US Government in 1965, and scientists from PAEC and ANL had led the construction. The Ayub Khan Military Government made then-science advisor to the Government, Abdus Salam, head of the IAEA delegation. Abdus Salam began lobbying for commercial nuclear power plants, and tirelessly advocated for nuclear power in Pakistan.Duff, Michael (2007). Salam + 50: proceedings of the conference, §Abdus Salam and Pakistan. London, United Kingdom: Imperial College Press. pp. 42. In 1965, Salam's efforts finally paid off, and a Canadian firm signed a deal to provide the 137MWe CANDU reactor in Paradise Point, Karachi.
In the Indo-Pakistani War of 1965, which was the second of four openly declared Indo-Pakistani wars and conflicts, Pakistan solicited Central Treaty Organization (CENTO) assistance,CENTO nation help sought by Pakistan. Chicago Tribune. 7 September 1965 but came under arms supply embargo in United Nations Security Council Resolution 211.The India-Pakistan War of 1965. Office of the Historian, Bureau of Public Affairs, United States Department of State Foreign minister (later Prime minister) Zulfikar Ali Bhutto aggressively began the advocating the option of "nuclear weapons programmes" but such attempts were dismissed by Finance minister Muhammad Shoaib and chairman Ishrat Hussain Usmani. Pakistani scientists and engineers' working at IAEA became aware of advancing Indian nuclear programme towards making the bombs. Therefore, In October 1965, Munir Khan, director at the Nuclear Power and Reactor Division of the International Atomic Energy Agency (IAEA), met with Bhutto on an emergency basis in Vienna, revealing the facts about the Indian nuclear programme and Bhabha Atomic Research Centre in Trombay. At this meeting Munir Khan concluded: "a (nuclear) India would further undermine and threaten Pakistan's security, and for her survival, Pakistan needed a nuclear deterrent...".
In 1969, after a long negotiation, the United Kingdom Atomic Energy Authority (UKAEA) signed a formal agreement to supply Pakistan with a nuclear fuel reprocessing plant capable of extracting of weapons-grade plutonium annually. PAEC selected a team five senior scientists, including geophysicist Dr. Ahsan Mubarak, who were sent to Sellafield to receive technical training. Later Mubarak's team advised the government not to acquire the whole reprocessing plant, only key parts important to building the weapons, while the plant would be built indigenously. The PAEC in 1970 began work on a pilot-scale plant at Dera Ghazi Khan for the concentration of uranium ores. The plant had a capacity of 10,000 pounds a day.
Development of nuclear weapons (Post-1971)
The Bangladesh Liberation War was a defeat for Pakistan, which led to it losing roughly of territory as well as losing more than half its population to the newly independent state of Bangladesh., Chapter 3, p. 87. In addition to the psychological setback for Pakistan, it had failed to gather any significant material support or assistance from its key allies, the United States and the People's Republic of China. Pakistan seemed to be isolated internationally, and in great danger; it felt that it could rely on no one but itself. Prime Minister Zulfikar Ali Bhutto was "obsessed" with India's nuclear programme, famously declaring that "We will eat grass, even go hungry, but we will have our own nuclear bomb." During this early phase of the programme Bhutto also sought financial and political support from friendly Muslim and Arab states, and countries such as Libya and Saudi Arabia provided financial assistance that helped sustain Pakistan's nuclear effort. At a United Nations Security Council meeting, Bhutto drew comparisons between the Instrument of Surrender that ended the 1971 war, and the Treaty of Versailles, which Germany was forced to sign in 1919. There, Bhutto vowed never to allow a repeat.
Pakistan began developing nuclear weapons in January 1972 under Prime Minister Zulfikar Ali Bhutto, who delegated the programme to the Chairman of the Pakistan Atomic Energy Commission (PAEC) Munir Ahmad Khan with a commitment to having the device ready by the end of 1976.Weissman, Steve R. and Herbert Krosney, The Islamic Bomb. New York: Times Book). 1981: page 45.Chakma, Bhumitra, pg 42, The Politics of Nuclear Weapons in South Asia, Ashgate Publishing Company, Burlington, VT, USA, 2011 At the Multan meeting on 20 January 1972, Bhutto stated, "What Raziuddin Siddiqui, a Pakistani, contributed for the United States during the Manhattan Project, could also be done by scientists in Pakistan, for their own people". Siddiqui was a Pakistani theoretical physicist who, in the early 1940s, worked on both the British nuclear programme and the Manhattan Project.
In December 1972, Dr. Abdus Salam directed a secretly coded memo to Pakistani scientists working at the International Centre for Theoretical Physics (ICTP) in Italy to report to the Chairman of the Pakistan Atomic Energy Commission (PAEC), Munir Ahmad Khan, informing them about the programme what was to be equivalent of the US "Manhattan Project." In an effort to instil a sense of pride, Salam noted that the heads of the Manhattan Engineer District were theoreticians, and informed the scientists at ICTP that a similar division was being established at PAEC; this marked the beginning of the "Theoretical Physics Group" (TPG). Other theoreticians at Quaid-e-Azam University would also join the TPG, then led by Salam who had done ground-breaking work for TPG. Among them was Riazuddin, Fayyazuddin, Masud Ahmad, and Faheem Hussain who were the cornerstone of the TPG.
Tedious mathematical work on fast neutron calculations, relativity, complex hydrodynamics and quantum mechanics were conducted by the TPG led by Salam until 1974 when he left Pakistan in protest, though he kept close contact with TPG. No such endeavours of the kind had taken place in the country and computerised numerical control (CNC) and basic computing facilities were non-existent at that time (though later acquired). For this purpose, the calculations on the high-performance computing and numerical analysis were performed by Dr. Tufail Naseem, a PhD graduate in mathematics from Cambridge University, assisted by other members of Mathematics Division– the division of pure mathematics at PAEC under Dr. Raziuddin Siddiqui and Asghar Qadir. About the lack of CNC facilities, Munir Ahmad Khan famously marked: "If the Americans could do it without CNC machines in the 1940s, why can't we do the same now.". With Abdus Salam departing, Munir Ahmad eventually led the TPG and assisted in the calculations. Two types of weapon design were analyzed: the Gun-type fission weapon and the implosion nuclear weapon. The programme turned to the more technically difficult implosion-type weapon design, contrary to the relatively simple 'gun-type' weapon.