Candover, Cinven, CVC Capital Partners and KKR have emerged as front runners in the race to buy the AA.

A source close to the deal said that with several private equity firms in the running, a trade sale was off the cards, ruling out bids from Norwich Union/Aviva and Royal Bank of Scotland Insurance.

"No one in the UK insurance industry has the £1.5bn that Centrica is reputed to want. A process with a non-financial services organisation is reaching conclusion and an announcement is expected in two weeks," said the source.

Centrica confirmed the Automobile Association (AA) was up for sale this week. The price tag is understood to be £1.5bn. The market approved of the move and Centrica saw its share price increase by 3.08% to 221.75p.

As well as its breakdown recovery business, the AA is Britain's eighth biggest insurance broker. The insurance broking business had a fee and commission income of £135m in 2002 and a profit of £20m.