ExxonMobil has formed an Arctic exploration partnership with Rosneft, the Russian state oil giant, in a strategic coup over rival BP.   In return Exxon, the world’s largest oil company by market capitalisation, will give the state-controlled Russian group minority stakes in projects in the US Gulf of Mexico, onshore fields in Texas and elsewhere.

The $3.2bn agreement follows this year’s collapse of an Arctic exploration deal between Rosneft and BP. The two companies’ aborted tie-up was blocked by the oligarch partners in BP’s existing Russian joint venture, TNK-BP.

It underscores international oil companies’ determination to explore and develop the Russian Arctic, one of the few places in the world with large, untapped oil and gas reserves, and Russia’s recognition that it needs international help to exploit those resources.

It also represents a success for Igor Sechin, the deputy prime minister in charge of energy issues who had lost face after the collapse of the BP deal earlier in the summer.   Mr Sechin was present at the signing ceremony at the ceremony in the Black Sea resort of Sochi, along with Vladimir Putin, Russian prime minister, and Rex Tillerson, Exxon’s chairman and chief executive.

Under the agreement, the two companies will together invest $3.2bn in exploring the Arctic Kara and Black seas. They also plan to invest $450m in a centre St Petersburg-based research centre. The three offshore blocks in the Russian Kara Sea are the same ones that Rosneft planned to explore with BP.

Mr Putin said Exxon “has unique technology” for work in the Arctic. “I was surprised that one of your platforms was able to withstand being struck by a 1m ton iceberg,” he said.

Mr Tillerson, Exxon’s chairman and chief executive, said the agreement represented “a significant strategic step by both companies.” He added that Exxon had been encouraged by the Russian government’s pledge to reform oil taxation and improve investment conditions for foreign and Russian oil companies.

The US group has previously encountered Russian opposition over its plans to sell China gas from the offshore Sakhalin 1 project – also a joint venture with Rosneft – in Russia’s far east.

Mr Sechin said the Exxon-Rosneft agreement forsaw $200bn-$300bn in direct investment over ten years. “One ice proof platform costs $15bn minimum” he said. “For the Kara Sea we require at least 10 platforms.” He declined to say when the first oil could be expected.

“The deal is huge for Rosneft,” added a senior banker involved in the deal. “There are only 3 companies in the world that they would cooperate with to get the right technology and experience, and they got the world leader. This is much better than BP.”

Rosneft had been courted by several foreign oil companies interested in Arctic exploration, including Royal Dutch Shell, but described the Exxon deal as “strategic and exclusive”.

Rosneft opened talks with ExxonMobil immediately after the Russian shareholders in TNK-BP challenged its proposed Arctic exploration and share swap deal with BP.

Exxon and Rosneft have agreed in principle to explore jointly in the US and other countries, with the Russian company taking stakes of up to 33 per cent, but no specific projects have been identified yet.

Alexander Burgansky, head of research at Otkritie, the Moscow investment bank, said the deal was a setback for Gazprom, the state-controlled gas export monopoly which has feuded with Exxon over the Sakhalin gas project since 2006.

(c) Isabel Gorst and Charles Clover in Moscow and Ed Crooks in New York