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Nuclear weapons now illegal!

The Treaty on the Prohibition of Nuclear Weapons entered into force on the 22nd of January, 2021. Nuclear weapons are now illegal under international law.

The TPNW is the first treaty to comprehensively outlaw nuclear weapons and provide a pathway for all nations to pursue the elimination of nuclear weapons. It is a crucial piece of international law that puts nuclear weapons in the same illegal category as biological weapons, chemical weapons, anti-personnel landmines and cluster munitions.

Entry into force (EIF) is an important milestone on the path to a nuclear weapon-free world. It makes concrete the standard that nuclear weapons are illegal and illegitimate for all states. It marks the moment that the treaty becomes a permanent part of international law.

State parties to the treaty are now bound by its prohibitions and obligations. A treaty in force can influence the behaviour of states not party, as evidenced by other weapons prohibition treaties.

Entry into force of the TPNW should compel financial institutions to operate in line with international law on nuclear weapons by excluding their producers from their investment universe. The TPNW prohibits assistance with the production of nuclear weapons, which includes financing.