MOSCOW — Russia will not sign a new treaty with the United States to replace the agreement limiting each side’s strategic nuclear weapons that expires in 2026, the Izvestia newspaper reported on Tuesday, citing an unidentified senior Russian source.

The New Strategic Arms Reduction Treaty, or New START, is the last remnant of efforts to slow the nuclear arms race between the former Cold War superpowers and increase transparency by imposing verifiable limits on the number of weapons.

President Vladimir Putin in 2023 suspended Russian participation in the treaty due to U.S. support for Ukraine, though Moscow has kept to the warhead, missile and bomber limits imposed by the agreement – as has the United States.

New START is due to expire on Feb. 5, 2026. There will be no replacement, Izvestia said.

“We suspended our participation in the START-3 treaty because of Washington’s actions,” it quoted the Russian source as saying. “And we will not sign a new agreement. Otherwise, it will only entertain the pride of the United States.”

The source said that the United States was supporting Ukraine and so there could be no new treaty.