Online gaming firms are facing a major crisis today after the US Congress passed legislation to ban online gaming there.
US Congress unexpectedly approved a bill early on Saturday that would make it illegal for banks and credit-card companies to make payments to online gambling sites.
The House of Representatives and Senate approved the measure and sent it to President Bush to sign into law. Most analysts think his approval is certain.
Britain's Partygaming, operator of leading online poker site Partypoker.com, and rivals Sportingbet and 888 said they would probably pull out of the United States and warned on future profits.
Partygaming's shares fell 59 per cent by this morning, Sportingbet lost 64 per cent, 888 was down 45 per cent and gaming software provider Playtech fell 55 per cent.
Austria's bwin.com Interactive Entertainment fell as much as 22 per cent in the first few minutes of trading.
Partygaming generates about 78 per cent of its revenue from the United States, while Sportingbet generates about 62 per cent there.
"If the President signs the act into law, the company will suspend all real money gaming business with US residents, and such suspension will continue indefinitely, " Partygaming said in a statement.
Partygaming's smaller rival Sportingbet said the likely ban would hit trading, and that it had scrapped a planned merger with World Gaming as a result of the legislation.