The Kremlin said on Wednesday it would provide details if and when Russian president Vladimir Putin spoke to British prime minister Boris Johnson by phone and that Mr Putin was ready to talk to anyone, including the "utterly confused".
Mr Putin and Mr Johnson were meant to talk on Monday, but Mr Johnson had to postpone due to domestic political problems.
Mr Johnson travelled to Ukraine on Tuesday, where he accused Mr Putin of holding a gun to Kyiv's head in a bid to bully the West into redrawing the post-Cold War security map of Europe.
Russia has said it has no plans to stage a new invasion of Ukraine, despite amassing tens of thousands of troops in reach its border.
Plans to hedge against US sanctions
The Kremlin also said on Wednesday that Russia had plans in place to hedge against possible US sanctions and urged the White House to stop "whipping up tensions" in Europe.
Washington and Nato have so far refused to give Moscow guarantees it is seeking that the Western military alliance will stop expanding and will not deploy offensive weapons to Ukraine.
The United States has said it will impose sanctions in the event of a new Russian invasion of Ukraine.
Kremlin spokesman Dmitry Peskov said Washington's behaviour was unpredictable and that Moscow was preparing to mitigate the effect of any such sanctions.
He said there were no immediate plans for a second round of Russia-US talks on the security guarantees sought by Moscow.
