Russia's state-run news agency RIA Novosti reports that Rosneft and Exxon "set up a tender for the design and construction of oil rigs that would facilitate their exploration of the arctic shelf."
Exxon Mobil and Rosneft in August signed a sweeping deal that included development in parts of the Black Sea and the South Kara Sea in the Russian arctic.
A seismic survey in the Russian waters of the Black Sea began in September under the terms of the strategic agreement. The Russian report estimates there are as much as 85 billion barrels of oil in the Kara Sea.
U.S. supermajor Chevron abandoned its Black Sea project in June, saying it had reservations about the reserve potential touted by Rosneft. The company was said to be upset with the terms of the venture, arguing it would carry all the exploration costs but have only a 33 percent stake in the operating company.