A US requirement for visitors to be fingerprinted and photographed is being expanded to include citizens from America's closest allies.
Millions of fingerprints are being checked each year
The move will affect visitors from 27 countries - including the UK, Japan and Australia - whose nationals are able to visit the US without a visa.
The change in the US-Visit programme is due to take effect by 30 September.
The programme is designed to fight terrorism, but has been criticised by many - notably in Latin America.
The US-Visit (US Visitor and Immigrant Status Indicator Technology) security system is meant to identify travellers who have violated immigration controls, have criminal records or belong to groups listed as terrorist organisations by the US.
The US has been routinely fingerprinting and face-scanning foreign visitors since January.
But Washington decided to extend the programme after determining that visa waiver countries will not
meet an October deadline to introduce sophisticated passports, which include biometric data and make counterfeiting virtually impossible.
The UK authorities, for example, have said they will not be able to issue the new passports with the new data - such as an individual's fingerprints or iris pattern - before mid-2005.
Andorra, Australia, Austria, Belgium, Brunei, Denmark, Finland, France, Germany, Iceland, Ireland, Italy, Japan, Liechtenstein, Luxembourg, Monaco, Netherlands, New Zealand, Norway, Portugal, San Marino, Singapore, Slovenia, Spain, Sweden, Switzerland, UK
The administration announced on Friday that it would seek a two-year extension of the deadline from Congress.
Security officials said the delay of the new passport system meant the port-of-entry security checks would therefore have to be extended.
Citizens from the 27 countries will still be allowed to visit the US without a visa, although they will now have to be fingerprinted and photographed before they enter.
"We recognise that the visa waiver country travellers are among our best allies, friends, and international guests," said Asa Hutchinson, undersecretary for border and transportation security.
"We are doing all we can to make sure the security measures cause minimal inconvenience."
The plans, if approved by Congress, will entail a massive increase in the visitors to the US requiring checks. Some 13 million visitors from visa waiver countries visit the US each year, compared to some 19 million from non-visa waiver countries.
Canadians will now be the only foreign nationals able to enter the US without the checks, Mr Hutchinson said.
Asked whether the data on visitors would be kept, Mr Hutchinson said it would - in part to "facilitate travel" for frequent visitors to the US.
He said fingerprints were checked against criminal databases, but the information was "strictly protected under privacy rules".
When the border procedures for non-visa waiver countries were introduced at the beginning of the year, Brazil protested by introducing similar checks for US visitors to Rio de Janeiro.
But the US authorities the news measuers do not add any significant time to the process of clearing immigration.
And the BBC's Washington correspondent Justin Webb points out that there may be some benefits.
Some people who were going to have to get visas will be allowed to continue using the scheme.