Royal Dutch Shell plans to put three oil and gas assets in the North Sea up for sale, as it seeks to ramp up disposals and focus on improving shareholder returns after a shock profit-warning.

Like its industry peers, Shell has been facing increasing investor pressure to rein in spending as costs rise and oil prices wane.

Glen Cayley, the Anglo-Dutch company’s vice president of its upstream business in Europe, has spoken to staff about the proposed sell-off of its Anasuria, Nelson and Sean platforms in the British part of the North Sea.

Together, the assets account for about two per cent of Britain’s oil production. Output from the North Sea basin has been in decline since 1999, raising concerns that the biggest companies could turn their backs on it, but Shell said it was committed to the area.

“These changes are very much in line with our strategy and will allow us to shape our future and focus on where we can add value to ensure a long-term future for Shell in the basin,” Cayley said.

Shell, attempting to win round investors after a major profit warning early this year, is targeting $15 billion of disposals over the next two years as it tries to deliver more attractive returns to shareholders.

According to a report in Britain’s Guardian newspaper, the North Sea disposals were not influenced by the upcoming September 18 referendum on Scottish independence, which other energy bosses have signalled is further undermining the North Sea investment climate.