Russia, which has unnerved the West with a troop buildup near Ukraine, last week unveiled a wish list of security proposals it wants to negotiate, including a promise NATO would give up any military activity in Eastern Europe and Ukraine.

The United States and Ukraine say Russia may be preparing an invasion of its ex-Soviet neighbour. Russia denies that and says it is Ukraine's growing relationship with NATO that has caused the standoff to escalate.

President Vladimir Putin said on Thursday Russia wanted to avoid conflict but needed an "immediate" response from the United States and its allies to its demands for security guarantees. Moscow has said it expects talks with US officials on the subject to start next month in Geneva. 

US President Joe Biden's administration has said some of Russia's security proposals are obviously unacceptable, but that Washington will respond with more concrete ideas on the format of any talks.