Russia's military said Tuesday some troops were returning to their bases following exercises near Ukraine, in a move that could lead to de-escalation amid fears of a Russian invasion of its neighbor country.

In another possible sign of easing tensions, Russian President Vladimir Putin said after a meeting with German Chancellor Olaf Scholz that Moscow is prepared to continue talks with the United States and NATO on measures to address their security concerns in Europe.

Tensions have been running high as Russia has amassed some 150,000 troops near Ukraine, a massive military buildup that follows its annexation of Crimea in 2014. The United States has been issuing warnings that a Russian military action could be imminent, possibly even occurring before the end of the Beijing Winter Olympics on Sunday.

Combined photo shows U.S. President Joe Biden (L) and Russian President Vladimir Putin. (Getty/Kyodo)

In Washington, U.S. President Joe Biden said his government should give "diplomacy every chance to succeed," but noted that Russia's partial troop withdrawal has not yet been verified.

"Indeed, our analysts indicate that they remain very much in a threatening position," Biden said at the White House, adding, "An invasion remains distinctly possible."

Secretary of State Antony Blinken, in a phone call with his Russian counterpart Sergey Lavrov earlier Tuesday, reiterated Washington's ongoing concerns that Moscow has the capacity to launch an invasion of Ukraine "at any moment" and emphasized the need to see "verifiable, credible, meaningful de-escalation."

Russia has been asserting that its security is under threat with NATO's eastward expansion and the possibility of Ukraine's membership in the alliance, although it has denied its intention to invade the former Soviet Union republic.

The United States has demanded Russia de-escalate by removing its troops from the border, while rejecting Moscow's key demand to offer a security guarantee precluding Ukraine's entry into NATO.

But at the same time, Washington has suggested room for discussions with Russia on setting reciprocal limits on military exercises in Europe and missile placement.

Putin said Tuesday that Moscow is ready to engage in talks on limiting the deployment of intermediate-range missiles in Europe, practicing transparency with regard to military drills and pursuing other confidence-building measures, according to The Associated Press.

But he also emphasized the need for the West to heed Russia's main demands, the news agency said.

Biden said at the White House that he believes "there are real ways" to address respective security concerns, but that the United States will "not sacrifice basic principles."

U.S. President Joe Biden speaks at the White House in Washington on Feb. 15, 2022. (UPI/Kyodo)

"Nations have a right to sovereignty and territorial integrity. They have the freedom to set their own course and choose with whom they will associate. But that still leaves plenty of room for diplomacy and for de-escalation," he said.

The United States and its allies, including Japan, have been engaging in efforts to seek a diplomatic solution to the Ukraine standoff, while warning of the "swift" and "forceful response" Russia could face if it pushes ahead with military aggression, indicating economic and other sanctions.

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