UK-based online gaming companies began folding the cards on their US operations as President George W. Bush signed a bill banning Internet gambling there, an Associated Press report said.
The report said the closure of potentially the most lucrative market in the world was a severe blow to the nascent online gambling industry, with those companies not facing complete collapse still reeling from the costs of exiting the US.
The North American market accounted for the vast majority of earnings of London-based Internet gaming companies and they were caught by surprise two weeks ago when US Congress passed the Unlawful Internet Gambling Enforcement Act, making it illegal for banks and credit card companies to settle payments to online gambling sites, the report said.
Shares in gaming companies sank rapidly after that announcement, and Bush provided the final hit when he signed the measure into law as part of a bill aimed at improving port security, the report further said.
Sportingbet and Leisure & Gaming both sold their US operations for a token $1 last week. World Gaming directors resigned, leaving the company in the hands of administrators, the report said.
PartyGaming, the world's largest gambling company, said it had suspended all real money gaming activities to customers in the US, the report added.
Empire Online said it would focus on gaming outside the US, while 888 Holdings said it was considering its options.
The loss of US business was crippling, as US residents accounted for half a market that was estimated to be worth $15.5 billion (12.35 billion euros) this year in 'spend' value, the report said.