Many online gaming firms have withdrawn from the US

It said that legislation making it practically illegal to trade in the US - where it had generated 75% of its earnings - had proved a "bitter blow".

Profits were $138.9m (�70.8m) - after the firm spent $250.4m on reorganising costs - mainly after the US ruling.

However, business elsewhere was in "excellent shape", it said.

Illegal

Like other gaming firms including 888.com and Sportingbet, Gibraltar-based Partygaming withdrew from the US and began focusing on other markets.

In October, President George W Bush signed the Unlawful Internet Gambling Enforcement Act - making it, in effect, illegal for firms to collect money there.

Total revenue from its websites - which include PartyGammon.com and EmpirePoker.com as well as the Partygaming brand, was up 13% to $1.1bn (�561m).