Airline passengers are to undergo facial scans at British airports for the first time in an attempt to improve security and reduce overcrowding, the government said yesterday.

Unmanned gates with computers will be brought in for holders of new UK and EU biometric passports to scan their faces and match them to records.

If the pilot scheme introduced in the summer is successful, it will be extended to all major UK airports, said the Home Office.

The new technology will be more effective at screening passports and preventing identity fraud, border security officials believe.

However, critics claim the plan is based on unproven technology that could cause innocent passengers even further delays. There is also concern passengers would be outraged at being rejected at an automated gate.

To ensure no-one wanted by police or other security agencies slips through, it is thought the new scanners will err on the side of caution, and may produce a small number of "false negatives" - innocent travellers rejected because the machine cannot match their face to the records.

Rejected passengers may then be redirected to desks staffed by passport officers for further checks.

Campaign group NO2ID condemned the plans. National co-ordinator Phil Booth said: "Someone is extremely optimistic. The technology is just not there.

"These technologies are only being introduced to make it easier to collect and track personal information about travellers," he said.

"People shouldn't be fooled by ministers' fairy-tale claims about biometrics, but should rather be asking where their personal details are being sent and why. Transmitting your passport data, home address, and even credit card details abroad shows contempt for your security. And waving a camera in your face while doing it is just misdirection."

Gus Hosein, a specialist at the London School of Economics in the interplay between technology and society, described it as "laughable technology".

He said: "US police at the SuperBowl had to turn it off within three days because it was throwing up so many false positives. The computer couldn't even recognise gender. It's not that it could wrongly match someone as a terrorist, but that it won't match them with their image. A human can make assumptions, a computer can't."

Liam Byrne, the Home Office minister for immigration, said the UK's border security was among the toughest in the world.

"Tougher checks do take time," he said, "but we don't want long waits, so the UK Border Agency will soon be testing automatic gates for British citizens. We will test them this year, and if they work put them at all key ports."

Plans for the summer trial emerged at a security conference in London.

A Home Office spokesman said it would publish details of how the technology worked, where the trials will be set up and the timescale for introducing the technology at a future date.

Earlier this month, the federal government in Australia gave the go-ahead to the a multi-million pound facial recognition project called SmartGate - after encountering problems with the technology.

SmartGate Series 1 is now scheduled to operate at Melbourne International Airport by the end of May and the rollout to five more airports will occur during this year and next. The system, is similar to that to be trialled in the UK, and involves matching a live image of the traveller against a digitised photograph stored on a microchip embedded in the passport. If the images match, the traveller is cleared through the control point.