Russian lawmakers voted on Tuesday to revoke Moscow's ratification of the Comprehensive Nuclear Test Ban Treaty, moving closer to abandoning a landmark agreement that outlaws the testing of nuclear weapons.

The move comes after President Vladimir Putin said earlier this month he was "not ready to say" whether Russia needed to carry out live nuclear tests.

Results from the State Duma lower house showed lawmakers unanimously approved the bill in its first reading.

The bill can be signed into law by Putin after passing three readings in the lower house and receiving approval in the upper house.

The treaty aimed to comprehensively ban all nuclear tests and explosions, after the Soviet Union, United States and other nuclear powers carried out over 2,000 tests during the Cold War.

Both Russia and the United States signed the treaty in 1996, but Washington never formally ratified the agreement.

Russia's top lawmaker Vyacheslav Volodin said earlier this month that Moscow would move to revoke ratification in a "mirror response" to the United States.

Since the start of Moscow's offensive in Ukraine, tensions have grown over the possible use of nuclear weapons in the conflict.

Putin mobilized Moscow's nuclear forces shortly after the conflict began and has repeatedly invoked Russia's nuclear doctrine, which allows the use nuclear weapons if the state faces a "threat to its existence".

During the summer, Putin confirmed Russia had sent tactical nuclear arms to its ally Belarus which borders Ukraine.

Earlier this month, Moscow said it had successfully tested a nuclear-powered cruise missile.