The sale of the Holstein Field, comprised of Green Canyon Blocks 644, 645 and 688 in the Gulf of Mexico, is part of continuing practice of reviewing the existing portfolio and evaluating new opportunities, the company said.

The Holstein Unit, anchored in 1,350m (4,400 feet) water depth, was first produced in December 2004, in which Shell holds a 50%interest and BP operates the unit with the ownership of the remaining 50%.

The deal, which is effective from 1 October 2012 will close by year-end 2012.