MOSCOW, July 16 (RIA Novosti) - The Russian oil pipeline operator Transneft, the Russian-British joint oil venture TNK-BP, and Russia's largest crude producer Rosneft have signed a swap agreement on oil supplies to cut their costs, Transneft said Wednesday.

The agreement stipulates the annual supply of 13 million metric tons (95 million barrels) of crude from East Siberia's Vankor deposit, currently being developed by Rosneft, to the Ryazan refinery in central Russia owned by TNK-BP, Transneft said.

In turn, TNK-BP will supply crude from its Samotlor field in West Siberia to Taishet in the Far East and further along the route of the East Siberia - Pacific Ocean (ESPO) pipeline, currently being built by Transneft, and also to Rosneft's refinery in Angarsk in East Siberia.

The East Siberia-Pacific Ocean pipeline project is designed to pump up to 1.6 million barrels of crude per day from Siberia to Russia's Far East, and then on to the energy-hungry markets of Asia.

The scheme will come into effect from 2010 when the first stage of the ESPO project goes online.