Details of travellers to the US will need to be supplied 48 hours in advance of trips from next year, heightening fears of a fall-off in transatlantic business travel.
Passenger details are currently forwarded on departure, with airlines such as British Airways penalising travel agents that fail to supply sufficient information in advance.
President George Bush signed legislation tightening the existing restrictions this week. The new rules apply to visitors from countries such as the UK that are covered by the US visa-waiver programme.
The US already has some of the tightest restrictions on entry in the developed world and insists on considerably more advance passenger information than required by a similar European Commission scheme.
Spain became the first EU country to demand advance information in June, ahead of its introduction across Europe next year.
US immigration authorities said the recent attacks in Glasgow and London confirmed the existence of terrorist cells in the UK.
Concern about the level of security checks at US immigration is believed to have depressed the market from the UK despite the dollar trading at more than two to the pound.
Figures from the Travel Industry Association of America suggest a fall of up to 3% in UK visitors last year. However, the TIA welcomed provisions in the new legislation to widen the visa-waiver programme and cut queues at immigration.
Travel to the US from non-waiver countries has fallen by almost one-fifth as restrictions have tightened, leading the US tourism industry to consider plans to raise $300 million through a tax on travel to fund improvements at airports.