Nuclear

In the mid-1970s, Pakistan took the uranium enrichment route to acquiring a nuclear weapons capability under the direction of A.Q. Khan. By the mid-1980s, Pakistan had a clandestine uranium enrichment facility, and Khan would later assert that the country had acquired the capability to assemble a first-generation nuclear device as early as 1984. [1] Islamabad conducted nuclear tests in May 1998 shortly after India, subsequently declaring itself a nuclear weapon state. Pakistan is not a party to the Treaty on the Non-Proliferation of Nuclear Weapons (NPT). The country has also refused to sign the Comprehensive Nuclear Test Ban Treaty (CTBT), and has blocked consensus at the Conference on Disarmament on starting negotiations for a Fissile Material Cutoff Treaty (FMCT).[2] According to 2011 estimates by the International Panel on Fissile Materials (IPFM), Pakistan has accumulated a stockpile of 2.75 ± 1 tons of highly enriched uranium (HEU) and 135 ± 45 kg of weapon-grade plutonium.[3] United States intelligence estimates in 2011 put the number of stockpiled nuclear warheads at between 90 and 110.[4]

Biological

Pakistan signed the Biological and Toxin Weapons Convention (BTWC) in April 1972 and ratified it in 1974. Credible open source literature suggests Pakistan has neither biological weapons nor a biological weapons program. The country does possess significant dual-use biotechnology capabilities, including well-equipped laboratories and trained scientists.

Chemical

Pakistan signed the Chemical Weapons Convention (CWC) in 1993 and ratified the treaty in 1997. Credible open source literature suggests Pakistan has neither chemical weapons nor a chemical weapons program.

Missile

Pakistan is developing both solid- and liquid-fueled ballistic missiles, based extensively on foreign systems, including those from China and North Korea. Nuclear-capable ballistic missiles inducted by Pakistan into its strategic forces include the Ghaznavi (Hatf-3, range 400km); the Shaheen-I (Hatf-4, range 750 km); and the Ghauri (Hatf-5, range 1,200km).[5] Missiles under development include the Shaheen-II (Hatf-6, range 2,000 km); the Shaheen-IA (an upgraded Hatf-4, range 2,500-3,000km); and the Nasr (Hatf-9, range 60km), a short-range missile tested in May 2012 with the stated capability to "add deterrence value… at shorter ranges."[6] In addition to ballistic missiles, cruise missiles are increasingly part of Pakistan's nuclear delivery plans, including the ground-launched Babur (Hatf-7, range 600km), and the air-launched Ra'ad (Hatf-8, range 350km), which have each been tested several times.[7] In September 2012, Pakistan Navy tested Surface to Air Missiles to enhance its operational capacity.[8]

Sources:
[1] "Interview with Abdul Qadeer Khan," The News (Islamabad), 30 May 1998, http://nuclearweaponarchive.org.
[2] "Pakistan Rules Out Test Ban Treaty Endorsement," Global Security Newswire, 19 June 2009, www.nti.org; and "Statement by Ambassador Zamir Akram, Permanent Representative of Pakistan at the Conference on Disarmament (CD)," Geneva, 27 August 2009, www.reachingcriticalwill.org.
[3] "Global Fissile Material Report 2011," International Panel on Fissile Materials, Sixth Annual Report, January 2012, www.fissilematerials.org.
[4] David E. Sanger and Eric Schmitt, "Pakistani Nuclear Arms Pose Challenges to U.S. Policy," The New York Times, 31 January 2011, www.nytimes.com.
[5] Hans M. Kristensen and Robert S. Norris, "Pakistan's Nuclear Forces, 2011," Bulletin of the Atomic Scientists, Vol. 67 No. 4, July/August 2011, http://bos.sagepub.com; "Pakistan Successfully Test-Fires Hatf-IV Ballistic Missile," DAWN (Pakistan), 25 April 2012, http://dawn.com; "Press Release No PR98/2012-ISPR," Inter Services Public Relations, 25 April 2012, www.ispr.gov.pk.
[6] "Press Release No PR94/2011-ISPR," Inter Services Public Relations, 19 April 2011, www.ispr.gov.pk; "Pakistan Successfully Test-Fires Hatf-IV Ballistic Missile," DAWN (Pakistan), 25 April 2012, http://dawn.com; "Pak Tests Nuclear-Capable Short Range Hatf-IX Missile," Indian Express, 29 May 2012, www.indianexpress.com.
[7] Hans M. Kristensen and Robert S. Norris, "Pakistan's Nuclear Forces, 2011," Bulletin of the Atomic Scientists, Vol. 67 No. 4, July/August 2011, http://bos.sagepub.com.
[8] “Pakistan Navy Test-fires Surface-to-air Missiles,” Daily Times (Pakistan), 30 September 2012, www.dailytimes.com.pk; “Pakistan Navy Testfires Missiles,” Gulf News (UAE), 29 September 2012, www.gulfnews.com; “Pakistan Navy Successfully Test-launches SAMs”, The Nation (Pakistan), 29 September 2012, www.nation.com.pk.