Reuters quoted a senior US Department of Defense official as saying that the Russian military had withdrawn 95 percent of its troops stationed at the border into Ukraine.
"We do not believe that a ground or water attack on Odessa on the shores of the Sea of Azov is imminent," said a senior US military official, speaking on condition of anonymity.
Ukrainian President Volodymyr Zelinsky said on Sunday that Russian forces were preparing to bomb the southern city of Odessa.
Reuters quoted the Pentagon official as saying that the Russian military had fired 600 missiles at its targets in Ukraine since the beginning of its military operation. He also claimed that the Russian military pillar in the north of Kiev was still suspended.
The Pentagon official, speaking on condition of anonymity because he was not authorized to speak to Reuters, said Russian military leaders were still outside Kiev, Kharkiv and Chernihiv, trying to complete the siege but facing resistance from Ukraine.
He also said that the Pentagon is monitoring the situation in Mariupol and the conflict in the region.