Astana signed the Treaty on the Prohibition of Nuclear Weapons, Kazakhstan's Foreign Ministry announced on Saturday.
"Kazakhstan had participated actively in the elaboration and adoption of the treaty, which became the first legally binding document in the history of nuclear disarmament," the ministry said in a statement.
The agreement was signed by Permanent Representative of Kazakhstan to the UN, Kairat Umarov.
"Our country's denuclearization was not an accidental decision, but a well-considered and thoughtful act by a responsible state that has learned the horrors of nuclear tests which have resulted in sufferings with the worst possible consequences, even in the third generation," the statement said.
Kazakh President Nursultan Nazarbayev continues to urge the international community to achieve a world free of nuclear weapons despite unwillingness shown by some states, it added.
The treaty, which is a legally binding instrument to prohibit nuclear weapons, was adopted on July 7 in 2017 with the support of 122 UN member states.
Kazakhstan became the 57th signatory state.