The Black Sea is a sensitive security zone for Moscow as it is near the Crimean peninsula, which Russia annexed from Ukraine

Russia on Friday accused the United States of making ''aggressive moves'' in the Black Sea.

Calling the activity by the US military ''aggressive,'' the Russian defence ministry said it ''posed a threat to regional and strategic stability.''

The Black Sea is a sensitive security zone for Moscow as it is near the Crimean peninsula, which Russia annexed from Ukraine in 2014.

Kremlin spokesman Dmitry Peskov dismissed as inflammatory a media report suggesting Moscow might be weighing an attack on Ukraine.

''Such headlines do nothing more than pointlessly and groundlessly fuel tensions. Russia does not pose a threat to anyone,'' said Peskov.

''We have repeatedly said that the movement of our armed forces on our territory should not be a cause for concern,'' he added.

Previously, a US naval command ship entered the Black Sea as part of NATO manoeuvres. The move was warmly received by Ukraine.

Pentagon spokesman John Kirby had said the US is monitoring the Ukraine region closely amid reports of a new build-up of Russian troops on the country's border.

"We're going to continue to consult with allies and partners on this issue... As we've said before, any escalatory or aggressive actions would be of great concern to the United States," Kirby said.

"We continue to support de-escalation in the region and a diplomatic resolution to the conflict in eastern Ukraine," he added.

Washington has refused to accept Russia's claim on Crimea and has delivered lethal military aid to Kiev for use in fighting the separatists.

Russian-backed separatists took control of Ukraine's eastern Donbass region in 2014. Soldiers on both sides continue to be regularly killed in the conflict there.