They opted to lose their flight, when told they could not board unless they passed through a full body scan. One of the women refused to be scanned on religious grounds, while her companion declined for "medical reasons.''

This is the first confirmed case in Britain of anyone being refused travel since mandatory body scanners were introduced in the country's busiest airports a month ago.

It also highlights some of the cultural and political implications of a potential EU-wide roll out of these scanners, currently being analysed by the European Commission.

The EU executive is expected to issue a report in April assessing their impact on health, privacy and the actual added value in terms of security.

Transport commissioner Siim Kallas has however already hinted that he is in favour of EU-wide rules and standards for this technology.

Currently, member states can introduce various models of full body scanners in addition to the existing screening methods deployed at their busiest airports.

Privacy rules differ, however. The X-ray devices used in Britain show the actual physical features, equivalent to a nude image, and have the capacity to store and print those scans.

Other versions in use in the Netherlands show a puppet image and only flash areas where metals or liquids are hidden. Amsterdam airport officials also offer the option of a physical pat-down in case the traveler refuses to go through the scan.

Italy on Thursday (4 March) also introduced a testing period for full-body scanners in Rome, starting with a terminal that serves US flights. The Italian devices are based on electromagnetic waves, because national legislation prohibits X-ray use other than for medical reasons.

Scanners with old X-ray technology are now on sale in the European Parliament's basement. The EU assembly acquired six such scanners in 2005 and never used them. The legislature is selling them now for half the price, with the winner of the tender expected to be announced next week.

MEPs in favour of EU standards

Meanwhile, MEPs dealing with home affairs and civil liberties have criticised the focus on scanning technology as a "quick fix" for major security blunders.

"It is stupid from a security point of view to allow member states to roll out such devices, we need standards at EU level," Belgian Socialist MEP Said Al Khadraoui said during an EUobserver tv debate on this topic. "We need to be clear that this body scanner is just an instrument, it won't guarantee full security and it costs a lot of money," he added.

Liberal British euro-deputy Sarah Ludford spoke about a recurrent pattern of law enforcement and security officials "failing to connect the dots" and to prevent major terrorist attacks such as the ones on New York and Washington in 2001.

The most recent case to prompt the strengthening of airport security occurred in December when a Nigerian who was actually on a "no-fly list" and whose own father reported concerns about his radicalisation, was allowed to board a US flight in Amsterdam, while carrying explosive devices.

"There is a danger if you just rely on technological quick fixes, you're not going to do the hard work, making sure the targeted info is truly shared in an appropriate manner and intelligence leads are followed up," Ms Ludford said.