National Lottery operator Camelot could change hands after major shareholders in the firm said they were considering selling their stakes.

Banknote printing group De La Rue and Japanese IT firm Fujitsu are looking at a possible sale of their 20% holdings in Watford-based Camelot, which has run the Lottery since it began in 1994.

Two fellow shareholders - Dairy Milk firm Cadbury and defence company Thales - have also been considering a sale, putting 80% of Camelot potentially up for grabs.

A spokeswoman for Thales, speaking on behalf of the other shareholders, said the quartet were "reviewing options for their interests in Camelot" although a sale was not inevitable.

She said: "The four shareholders have informed Camelot's board that, should a sale process result from this review, this would be subject to achieving an acceptable price for their shareholdings."

The fifth shareholder in Camelot, Royal Mail, is not taking part in the process, she added.

Camelot, which won the right to run the competition for another ten years in 2007, could be bought by an overseas lottery operator or private equity firm, the Sunday Telegraph says.

Any incoming shareholder would have to be approved by Camelot's regulator, the National Lottery Commission.

Camelot has raised around £22 billion for good causes so far. Ministers are also said to be keeping a close eye on the situation as Camelot is putting £2.2 billion towards the cost of London's 2012 Olympics.

Camelot said the potential stake sales "were a matter for the shareholders".