Britain's online bookmakers are expecting a multi-million-pound windfall as they tap into the lucrative but heavily regulated Far East sports betting market during the World Cup.

It is the first time the fledgling online industry has been in a position to take bets on the world's biggest sporting event and operators have been determined to woo traditionally high-spending Asian customers.

Leading UK website operators - including William Hill, Ladbrokes.com, Coral-owned Eurobet.com and Sportingbet.com - point out that Asian customers already dominate the global betting market for other sports.

Global gambling turnover for horse racing is thought to be £60bn a year, with Asia contributing more than half, according to analysts at Dresdner Kleinwort Wasserstein.

William Hill - which will tomorrow publish a price range prospectus for its forthcoming flotation - has estimated that British bookmakers could take up to £200m in additional bets during the World Cup, including a huge jump in online punts.

The company made a profit of £2m from Euro 2000 and £12m from the World Cup 98 in France. This time around, the bookmaker is said to be expecting profits between those two figures because of the unfavourable time difference.

Sportingbet, which operates exclusively on the internet, believes the fixture times will prompt many British punters to turn to the internet.

It also says that gamblers in many Asian states will be betting on reputable UK sites because independent high street bookmakers are illegal in Japan and Korea.

"For the first time, the internet will be their most accessible route to placing a bet," said chief executive Nigel Payne. He added that reaching Asian gamblers remained a problem because betting advertising was forbidden in many Far East countries.

One analyst pointed out that international football matches were often a disappointment to bookmakers because of the predictability of their outcome.

He said that the result of the opening game, between France and Senegal, did not appear likely to create the kind of uncertainties on which the gambling industry thrives.

Many online operators could even be preparing to make a loss on the World Cup, he said, using the event as a showcase for the new betting medium in front of an Asian market.

British firms benefited from the Treasury's decision last October to more than halve the tax burden on bookmakers.