Home Secretary Alan Johnson saw new automatic passport gates in operation at Gatwick Airport today.

Passengers with biometric passports can use the fast-track system to beat the queues at immigration.

The gates use facial recognition technology to match passengers with the electronic picture stored in their passport.

Details are also checked against police and terror watch lists.

Nearly one million passengers have passed through electronic gates at Gatwick, Manchester, Stansted, Cardiff and Bristol Airports, including 50,000 at Gatwick, since August.

Similar gates are due to be installed at Heathrow Airport next year.

Adults with a passport issued since 2006 can use the gates, but under-18s must pass through manual checks, in part as a guard against child trafficking.

UK Border Agency officials monitor the gates to stop passengers tailgating and deal with anyone rejected by the system.

Mr Johnson was unable to pass through the gates himself because he has an old-style passport issued before 2006.

He said the gates would improve security and convenience and allow "low-risk" passengers to get through more quickly.

He said: "Low-risk travellers, if they prefer not to queue up, can come through this automatic system provided they have a biometric passport.

"It's a very quick, easy and foolproof system and allows UKBA to concentrate on people coming in from countries where there's a problem with drug carriers, etc."

Passengers using the system said it was very fast.

French businessman Eric Laumonier, from Bordeaux, said: "It's good because I do not have to queue. It's very good, very fast."