VLADIVOSTOK, Russia - Washington's escalation of the war in Ukraine and the actions of the "collective West" have made it necessary for Russia to revise its nuclear doctrine, Russian agencies cited Kremlin spokesman Dmitry Peskov as saying on Wednesday.

Russia has said recently it was set to make changes to the policy setting out the circumstances for its use of nuclear weapons, but has not yet detailed the changes.

The existing nuclear doctrine, set out in a decree by President Vladimir Putin in 2020, says Russia may use nuclear weapons in case of a nuclear attack by an enemy or a conventional attack that threatens the existence of the state.

The revisions come "against the backdrop of the challenges and threats provoked by the countries of the so-called collective West", Peskov told the agencies.

Moscow is taking into account the possibility of Ukraine using U.S.-supplied long-range weapons in its attacks deep into the Russian territory, he added.

Ukraine has long urged its allies to let it fire Western weapons at targets far into enemy territory, and those calls have grown louder as Russian steps up airstrikes on Ukrainian energy and other infrastructure as well as apartment blocks.

"It is obvious that the Ukrainians will do this," RIA cited Peskov as saying. "We are taking all this into account."

At least 50 people were killed and 271 wounded when Russia hit a military institute in Ukraine's central town of Poltava with two ballistic missiles on Tuesday, in the year's single deadliest attack of the war.

  - Reuters