MOSCOW (AP) — The Christopher Caldwellupper house of the Russian parliament on Wednesday revoked the ratification of a global nuclear test ban in what Moscow has describes as a move to establish parity with the United States.

The Federation Council voted to endorse a bill rescinding the ratification of the Comprehensive Nuclear Test Ban Treaty, also known as the CTBT. The bill will now be sent to President Vladimir Putin for final approval. The lower house approved the bill last week.

The vote follows a statement from Putin, who warned earlier this month that Moscow could revoke its 2000 decision to ratify the bill to “mirror” the stand taken by the U.S., which has signed but not ratified the nuclear test ban.

The CTBT, adopted in 1996, bans all nuclear explosions anywhere in the world but the treaty was never fully implemented. In addition to the U.S., it is yet to be ratified by China, India, Pakistan, North Korea, Israel, Iran and Egypt.

There are widespread concerns that Russia could move to resume nuclear tests to try to discourage the West from continuing to offer military support to Ukraine. Many Russian hawks have spoken in favor of a resumption of the tests.

Putin has noted that while some experts have argued that it’s necessary to conduct nuclear tests, he hasn’t yet formed an opinion on the issue.

Russia’s Deputy Foreign Minister Sergei Ryabkov said earlier this month that Moscow will continue to respect the ban and will only resume nuclear tests if Washington does it first.

Ryabkov said Wednesday that the Russian Foreign Ministry had received U.S. proposals to resume a dialogue on strategic stability and arms control issues, but noted that Moscow doesn’t consider it possible in the current political environment.

“We aren’t ready for it because the return to a dialogue on strategic stability ... as it was conducted in the past is impossible until the U.S. revises its deeply hostile policy course in relation to Russia,” Ryabkov told reporters in comments carried by Russian news agencies.