Removing or restricting permits is the most severe penalty available to countries which have found major safety failings on foreign aircraft and are not satisfied that the necessary improvements have been undertaken.

The UK has, however, revealed that four of the 2002 bans were imposed in Switzerland, with one each in Belgium and the Netherlands.

Switzerland has confirmed to BBC News Online that 23 planes are currently banned, but says confidentiality laws and a "gentlemen's" agreement prevent it from naming the airlines involved, or even confirming how many of them there are.

A 24th plane was banned - the downed Flash Boeing 737.

Belgium has not commented on its 2002 case, and the Netherlands has denied banning or restricting a company that year.

The BBC's inquiries have revealed that the same Flash plane which plunged into the Red Sea on Saturday failed a Swiss safety test in October 2002 but passed a French one in Toulouse in 2003.

http://news.bbc.co.uk/2/hi/europe/3377953.stm