KIEV (REUTERS) - Russia's Black Sea fleet denied its forces were involved on Friday in seizing or blockading the Belbek military airport in Ukraine's Crimea region, Interfax news agency said.

"No units of the Black Sea fleet were deployed in the area of Belbek nor did they take place in blockading it," a statement from the fleet's press service said.

But it said it had stepped up measures by its "anti-terror units" to protect areas where parts of the fleet were located in Crimea and the living quarters of service personnel and families"given the unstable situation".