"We're seeing a small number now that appears to be moving away from Kyiv, this on the same day that the Russians say they're withdrawing," Pentagon spokesman John Kirby said.

"But we're not prepared to call this a retreat or even a withdrawal," he said. "We think that what they probably have in mind is a repositioning to prioritize elsewhere."

"We all should be prepared to watch for a major offensive against other areas of Ukraine," Kirby said. "It does not mean that the threat to Kyiv is over.

"Russia has failed in its objective of capturing Kiev," the Pentagon spokesman said, but "they can still inflict massive brutality on the country including on Kyiv."