Online gambling company 888 Holdings has received a takeover approach from Britain's biggest bookmaker William Hill, lifting its share price by more than 20 per cent.

The statement from 888 came after repors William Hill had held advanced talks over a £750 million offer as it looks to accelerate expansion of its online gaming operations.

An offer of 210 pence per share was suggested.

Shares in 888, which offers casino, poker and bingo games, were up 21 per cent at 175 pence by 3pm, with trading volumes nearly five times the stock's daily average. William Hill shares fell 3.5 per cent to 376.2p.

"The board of the company confirms that it received an approach regarding a possible offer for the company by William Hill," 888 said. "There can be no certainty, however, that any firm offer will be made."

888 saw a takeover by Ladbrokes collapse over pricing in 2011.

Panmure Gordon analyst Karl Burns said that a deal at 210 pence was already quite pricey and that William Hill would be unlikely to raise its offer.

"I think there is a good chance that the deal may not go through ... it would stretch their (William Hill's) balance sheet to a degree that they may have to raise capital as well."