BP has put its 10m-tonnes-a-year Coryton refinery in Essex for sale but the asking price has not been revealed.

The complex on the Thames Estuary is being sold as a going concern and there is not expected to be any impact on jobs, a BP statement said.

Coryton employs 550 staff and 500 contractors, and 75% of its output is petrol, diesel and aircraft fuels.

The British energy giant said it had decided to sell after a review "concluded that maintaining a smaller network of refineries in Europe would provide greater benefit".

BP said in a statement that it was holding initial discussions with a number of potential buyers and it expected the sale to go through later this year or the beginning of 2007.