U.S.-based utility Dynegy Inc said yesterday it had agreed to buy the natural gas storage subsidiary of Britain's BG Group Plc for £421 million in cash, expanding its European energy delivery network.

Under the terms of the deal Dynegy will buy BG Storage Ltd, whose assets include Rough - Britain's main natural gas storage facility, in the North Sea. The facilities used to be a regulated monopoly but were removed from direct regulation in 1999.

BG Storage owns 30 wells with five offshore platforms, nine salt caverns, about 30 kilometres of pipelines and an onshore natural gas processing terminal. When the deal closes, expected in the third quarter, BG Storage Ltd and its 260 employees will become part of Dynegy Europe Ltd.

Houston-based Dynegy also forecast 2002 earnings of $2.50 to $2.60 a share. The current Thomson Financial/First Call consensus estimate is $2.42. Dynegy said it expected the acquisition to add to its earnings in 2002 and contribute to its previously announced growth rate of 20 to 25 per cent per year.

"This acquisition is the cornerstone of Dynegy's European energy delivery network, which will enable us to capture incremental value in the newly liberalised European Union energy markets," said Gary Cardone, Dynegy Europe's president, in a statement.

BG Chief Executive Frank Chapman said his company would use the cash to grow its strategic position as an integrated gas company. "We have carried out an exhaustive strategic review of BG Storage's operations and concluded that the greatest shareholder value was likely to be achieved through a sale of these assets, and we have worked quickly to realise this outcome," he said in a statement.

BG said it had booked capacity until 2004 and would continue to do so in future to manage its upstream portfolio. The sale is subject to approval by Britain's energy regulator Ofgem and competition authorities. BG's shares were down 0.8 per cent at 278-1/2 pence by 1455 GMT, while Dynegy's shares gained 2.6 per cent to $49.50.