controlled Rosneft agreed to a share swap under which they plan to jointly explore for offshore oil and gas in a deal that gives the UK company access to areas of the Arctic previously reserved for Russian oil companies. BP, recovering from its Gulf of Mexico oil spill disaster, will swap 5 percent of its shares, valued at $7.8 billion, for 9.5 percent of Rosneft. The deal covers huge areas of the South Kara Sea in the Arctic that BP said could contain billions of barrels of oil and gas and had been previously off limits to foreign companies. The pact, which is expected to be completed in a few weeks, highlights a rebound in relations with Moscow both for BP and its Chief Executive Bob Dudley, who was forced to flee Russia in 2008 after heading BP's Russian joint venture, TNK-BP, which is half-owned by BP. Dudley said the deal was the first significant cross-shareholding between a nationally owned oil company and an international oil company and called it “a new template for how business can be done in our industry.” Russia is a key part of BP's global operation, providing the company with a quarter of its reserves before the US oil spill, so it is vital for Dudley to establish a good working relationship with the world's largest oil exporting nation. BP has a market capitalization of $150 billion, while Rosneft is valued at about $83 billion.