The announcement from the leader of breakaway Abkhazia comes on the back of several attacks by Ukrainian forces on Russia's Black Sea fleet that have embarrassed the Kremlin.

Both Moscow and Kyiv have escalated tensions on the key waterway since July, when Russia exited a deal guaranteeing safe passage for cargo ships to and from Ukraine's Black Sea ports.

"We have signed an agreement, and in the near future there will be a permanent point of deployment for the Russian navy in the Ochamchire district," Abkhazia's separatist leader Aslan Bzhania, told the Russian tabloid Izvestia.

He said the purpose of the deal was to "increase the defence capability both of Russia and Abkhazia," according to the interview published Thursday.

"And this kind of cooperation will continue, because this safeguards the fundamental interests of both Abkhazia and Russia. And security is above all," he added.

There was no immediate comment from Georgia's authorities, who have been accused by the political opposition of an increasingly pro-Kremlin streak, despite having fought a war with Russia in 2008.

Bzhania was in Russia this week to meet with Russian President Vladimir Putin, and during an earlier meeting with Russian Foreign Minister Sergei Lavrov, he voiced support for Russia's intervention in Ukraine.

- 'To the end' -

"You can be sure that we are with you to the end," he told Lavrov, according to Russian news agencies.

The Kremlin's spokesman Dmitry Peskov downplayed Bzhania's announcement on the naval base, and said he was unable to comment.

"Questions related to the deployment of our troops and our ships -- these are for the defence ministry," he told reporters.

Russia has permanent military bases stationed in Abkhazia and another Moscow-backed separatist region, South Ossetia, both of which it recognised as independent states in the wake of its war with the Caucasus country in 2008.

Ukraine last month struck the headquarters of Russia's Black Sea fleet on the annexed Crimean peninsula, marking a major blow for Moscow.

Kyiv said it killed the fleet's commander in the cruise missile strike, a claim it rolled back on after Russia released images showing the official attending a meeting of defence officials.

Reporting by Russian media, citing military and satellite imagery, suggested that Russia has begun withdrawing its warships from Crimea in the wake of several attacks.

The British defence ministry meanwhile said earlier this week that the Black Sea fleet's "activities" were increasingly being moved to a Russian naval base further east.

Warships are "likely relocating to Novorossiysk in the face of threats to Sevastopol," it said on social media.