British Prime Minister Gordon Brown has said full-body scanners are to be introduced at British Airports.
The airports' operator, BAA, said it would install the machines at London's Heathrow Airport as soon as possible.
Experts have questioned the scanners' effectiveness at detecting the type of bomb allegedly used on Christmas Day in an attempted plane attack over Detroit.
But Mr Brown said it was essential to 'go further' than the current technology allowed.
Meanwhile, the British and US embassies in Yemen have been closed in response to threats by al-Qaeda.
A statement on the US embassy website said: 'The US Embassy in Sana'a is closed today, January 3, 2010, in response to ongoing threats by Al-Qaeda in the Arabian Peninsula (AQAP) to attack American interests in Yemen.'
Earlier, the British and American governments have said they will jointly fund a counter-terrorism unit in Yemen following the alleged failed bomb airline attack over Detroit on Christmas Day.
Downing Street and the White House said they would also intensify efforts to tackle the emerging terror threat from Somalia.
President Barack Obama has alleged that the Christmas Day bomb suspect was trained by a Yemen-based al-Qaeda offshoot.
The US president has sent his top Middle East general to meet Yemen's president.
Michael Schuer, a former CIA agent and now a Professor of Security Studies at Georgetown University, says the two governments should have acted sooner.
