BP has agreed to sell its stake in a major North Sea gas pipeline system in a £324 million deal.

The company is to sell its equity in the Central Area Transmission System (Cats) business to Antin Infrastructure Partners, which already owns a majority interest in the operation.

The oil giant - the current operator of Cats - said securing the new owner will ensure a better future for the key piece of North Sea infrastructure.

Cats, a combination of pipeline and processing facilities, transports and processes gas on behalf of most of the major North Sea gas producers.

The infrastructure can handle more than 48 million cubic metres of natural gas each day.

The Cats pipeline begins at a riser platform in the central North Sea and transports gas some 250 miles (400km) to a processing terminal in Teesside on the north-east coast of England, according to its website.

BP said the agreement comprises a payment on completion of £302 million and a deferred amount of £22 million, subject to certain adjustments.

The sale will be as a fully operational business, with staff expected to transfer to the new employer.

BP said it is aiming to complete the sale before the end of the year.

Trevor Garlick, regional president BP North Sea, said: "The North Sea is an important region for BP.

"Our strategy here is to focus our resources and investment to create an efficient, sustainable and competitive business which will contribute to UK energy security for many years to come.

"Key elements of this are the completion of our major projects in the central North Sea and Shetland area, and continued management of our portfolio.

"Cats has been a great business for BP but, aligned to the recommendations of the Wood Review, we believe securing this new owner will ensure a better long-term future for this key piece of North Sea infrastructure.

"Supporting staff and ensuring continued safe operations will be our priority as we go through this transition period."

Construction of the Cats pipeline, which transports about 8% of the UK's gas demand, began in 1991, with first throughput in 1993.