New checks at airports 'will not be permanent'

"We don't want to give the impression that this is enduring," a Department of Transport spokesman said. "It is a response to the threat level and that has already dropped from critical to severe."

The decision on what measures are appropriate is made by the Joint Terrorism and Analysis Centre, comprising counter-terrorism agencies including MI5.

"We are working hard to change the position but there is no indication of when the threat level might be reduced," the spokesman said.

The department also said it had no plans to ask other countries to impose stricter checks on their passengers travelling to Britain, although there would be discussion this week about the lessons learned with European Union partners. Despite a stoical approach by the public, many of whom say they understand the measures are necessary, the department was keen to calm the anger of airlines over the increased checks.

"We are aware that it is making journeys uncomfortable for passengers and we will do anything we can to alleviate that," the spokesman said.

The airport operator BAA said that queues at its airports, including Heathrow and Gatwick, had not been unusually long but admitted that the number of travellers, normally estimated at up to a million for the bank holiday weekend, was only 780,000.

The effect on the number of travellers has prompted the chief executives at British Airways and Ryanair to criticise the procedures at airports.

BAA responded by indicating that passenger profiling, in which security officers attempt to single out those more likely to commit terrorism offences, is already in place behind the scenes.

"There is a multi-layered approach and what the public see is only the frontline," a spokesman said.

"Security includes a number of bodies such as the police, Special Branch, immigration service and the airlines that use CCTV, passenger profiling and immigration checks among other measures."

The changes have involved a reduction in the size of hand luggage so that it is quicker for staff to check through by hand and a ban on taking liquids and make-up through security checks. Those not flying to the US can buy bottles when they have passed through.

Body and hand luggage searches are stricter than usual but have been cut from checking every passenger in the days after the arrests of alleged terrorists on Aug 10.

BAA is recruiting extra staff to its 1,300-strong security operation. It said: "The security of passengers is our priority but in the long term we do not believe these measures are sustainable."

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