British bank Alliance & Leicester has received a takeover bid from an unnamed source, sending shares rocketing.
A&L, one of the UK's major financial services groups, said it is in discussions with a possible buyer about an offer of 317 pence per share, valuing the business at about £1.3 billion.
A former building society, the firm offers a broad range of financial services to personal and commercial customers.
Like other British lenders, it has been hurt by the credit crunch and has seen its share price slump in value.
Annual profits fall 30 percent last year following chaos in credit market, which forced it to write down the value of mortgage-backed investments by nearly £400 million.
It is not yet clear who is bidding but leading European banks such as Lloyds TSB, Banco Santander and Credit Agricole are seen as possible suitors.
Alliance told the BBC it had disclosed details of the bid "without consent".
Shares in the British bank have soared by more than 40 percent since the disclosure.