BP acquired the interests in the fields – Magnolia, Merganser, Nansen and Zia - from Devon Energy earlier in 2010 as part of a wider acquisition of assets in the Gulf of Mexico, Brazil and Azerbaijan.
Andy Hopwood, BP executive vice president, Strategy and Integration, said: "When BP acquired Devon's Gulf of Mexico assets it was clear that these four fields did not fit well with the rest of our business in the region. We therefore decided they would be of more value to another company than to BP."
Marubeni will pay BP $650m in cash for the interests, subject to customary post-closing adjustments.
The deal shoudl be completed early next year if regualtors give the go ahead, BP said.