London: Queen Elizabeth II opened Heathrow Airport's gleaming new Terminal 5 on Friday, a day after a security breach at the world's busiest international airport.

The queen and Prince Philip, toured the new facility under heavy security less than 24 hours after a man with a backpack scaled a Heathrow fence and ran onto an active runway, briefly impairing flight operations.

"This is a 21st century gateway for Britain," said the queen, who praised the new building as "environmentally responsible".

The queen, wearing a festive red hat, was met by executives from British Airways and airport operator BAA at the start of an extensive visit to the new facility, completed after more than five years of construction at a cost of £4.3 billion (Dh31.8 billion).

The monarch's decision to open Terminal 5 personally - just as she opened the airport's first passenger terminal in 1955 - reflects the importance of the new building, which officials believe will reverse the airport's reputation as a rundown, overcrowded facility.

Sir Nigel Rudd, chairman of BAA, greeted the queen.

Transportation Secretary Ruth Kelly called the building "a landmark structure" that would restore Heathrow's stature as a world-class airport.

The new terminal is designed to handle up to 30 million passengers per year and to alleviate congestion at Heathrow's other terminals, which are all slated for refurbishment or replacement in the coming years.

The inefficient baggage handling system at Heathrow's existing terminals has posed a major logjam for travellers, and officials said the new Terminal 5 system will be able to handle 12,000 bags per hour efficiently, without delays. Still, they acknowledged that unanticipated bugs in the entire terminal system would have to be worked out once actual flight operations begin on March 27.

Quick security checks

British Airways will be the only airline using the new terminal.

Said David Noyes, the airline's customer service director: "We expect there to be no more than one person in front of you at the express kiosks and the fast bag drops, so if you have checked in at home, it should take no more than 10 minutes from the time you enter the building to the time you clear security."