Russia's largest oil producer Rosneft has restarted exploration drilling on two large offshore blocks in the Kara Sea after managing to persuade Chinese operators to provide two drilling rigs, despite the risk of US sanctions.

Meeting with Russian President Vladimir Putin in Moscow on Tuesday, Rosneft executive board chairman Igor Sechin said wells had been spudded at the Vikulkovskaya structure on the East Prinovozemelsky 1 block and at the Ragozinskaya structure on the East Prinovozemelsky 2 block in the second half of July.