The US Government says all visitors must have a machine-readable passport - but it’s not a hard and fast rule, it appears.

Can you remind me of the new rules?

Since September, Britons using the Visa Waiver Programme (VWP) have been photographed and fingerprinted on arrival. The index fingers of all visitors aged from 14 to 79 are pressed on an inkless glass plate: the prints and photos are then archived for matching purposes on future visits.

And since October, every visitor to the US also requires individual, machine-readable passports with two lines of letters, numbers and chevrons on the page for personal details. An estimated 300,000 Britons do not have these passports, either because they have old-style versions issued abroad or are children included on a parent's passport. If you don’t have an MRP, then you must apply for a visa.

So I can’t get in without a MRP passport or visa?

That’s what we thought. At the 11th hour, in late October, the US said it would consider a “one-time exemption” for those without an MRP or visa. It appears a case of one strike and in - but you won’t get away with it on the next visit.

Who else needs a visa?

Four million Britons will visit the US this year, the majority of whom are holidaymakers who can stay for 90 days without a visa and can travel under the VWP. But 135,000 Britons will apply for a visa because they are students, have holiday homes in Florida, are business travellers who need to stay longer - or don’t have an MRP. You should also apply for a visa if you have a conviction, even if you have been arrested but not charged. It's a muddy area but clearly the US is not likely to ban you for a shoplifting conviction 40 years ago - but best to clear it up here, rather than be turned back at the entry airport.

Everybody who needs a visa must now be interviewed face-to-face at US consular offices in London or Belfast - previously applications could be made by mail. Improvements at the London offices mean that the four-week average to complete the visa process will be cut to a week. Visas cost around £55.

Phew. Any more rules in the offing?

I’m afraid so. Eventually, all Britons must have new-style biometric passports with face-recognition technology embedded. The US says this will come into force in October, 2005 - however, the British Government is unlikely to start trials until at least September. Be aware but don’t worry about it for a while.

Has the photo and fingerprinting exercise caused queues in the US?

US officials say that the process takes only 15 seconds per passenger - but with 45,000 international passengers arriving daily at JFK airport in New York, the aggregated time is self-evident. Early reports from British visitors suggest that queues have not been outrageous, however, and that US immigration officials are making a conscious effort to be more welcoming, despite early hiccups. One senior US official has acknowledged "unnecessary rudeness and hostility" towards visitors. But posters have since been stuck up in airports saying: "We pledge to treat you with courtesy, dignity and respect."

What’s the feedback from the US?

At a business travel conference in Stockholm in November, Jim Williams, director of the Department of Homeland Security's US-VISIT programme, told delegates that since fingerprinting and photos were introduced, the US had recorded more than 1,000 "hits" in matching entrants to the US with its watchlists of undesirable aliens. He added that US-VISIT has stopped "280 known criminals from coming in who shouldn't have come in." What he failed to answer was the question of whether the 720 who were not stopped from entering were erroneously targeted. Williams admitted: "We haven't stopped a terrorist yet."

Useful to know: The US Transportation Security Administration (www.tsa.gov) has just added a Security Checkpoint Wait Times guide to its website. Although the guide only covers departures, it provides a useful steer on optimum transit times for passengers booking a connecting flight and could influence your choice of airport. For example, fly back from New York on a Friday at 6pm and security checks at La Guardia could take up to 72 minutes; at JFK, a maximum of 19 is recorded. The guide is not comprehensive, however: there are no statistics for Newark, for example.

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