Pakistan began developing a nuclear weapons programme in the 1970s but apparently conducted its first test on 28 May 1998 when it detonated five separate devices. Momentum for the program was provided by Indian nuclear tests such as Smiling Buddha in 1974. However in 1999 Pakistan signed the Lahore Accords , with India, agreeing a bilateral moratorium on nuclear testing.

Weapons development takes places at Kahuta and Joharabad, where weapons grade plutonium is made; the latter allegedly with the assistance of Chinese technology. Estimates usually put Pakistan's nuclear deterrent at around 40 HEU (highly enriched uranium) warheads.

In 2002 Pakistan was accused of supplying nuclear technology to North Korea, an allegation which its military leader Pervez Musharraf admitted and caused the suspension of Pakistan's chief nuclear scientist.

Pakistan acceded to the Geneva Protocol on April 15, 1960, the Biological Weapons Convention in 1974 and the Chemical Weapons Convention on October 28, 1997. However Pakistan is not a signatory of the Non-Proliferation Treaty and, consequently, not bound by any of its provisions. Other non-signatories of the NPT include India and Israel.

Pakistan is currently the only predominantly Muslim country with nuclear capabilities.