WASHINGTON - US President Joe Biden said Tuesday that there was still time to resolve the Ukraine crisis through diplomacy but warned that sanctions are "ready to go" if Russian troops attack the country.

Biden said that despite Russia's claims earlier in the day, Washington and its allies had yet to verify the withdrawal of some of the 150,000 troops he said Moscow had mustered along Ukraine's border.

"Analysts indicate that they remain very much in a threatening position," Biden said in an address on the crisis.

"The United States is prepared no matter what happens. We are ready with diplomacy," the US leader said.

"And we are ready to respond decisively to Russian attack on Ukraine, which is still very much a possibility," he said, warning of "powerful sanctions."

Earlier, Moscow's defense ministry announced some soldiers and hardware were leaving the border region to return to their bases at the end of planned exercises.

After a meeting Tuesday with German Chancellor Olaf Scholz in Moscow, President Vladimir Putin said Russia "of course" did not want war, and was willing to look for solutions with the West.

"We are ready to work further together. We are ready to go down the negotiations track," Putin told a joint press conference with Scholz, confirming a "partial pullback of troops."