Ryanair has demanded a return to normal security practices at British airports within a week or it will pursue a claim for compensation.
However, the Department of Transport is facing down Ryanair's ultimatum.
In a statement this morning, the airline issued its ultimatum to the British government, saying that it had written to the Secretary of State for Transport to confirm it would not seek compensation under the Transport Act 2000 if the security checks returned to a normal level within seven days.
"The security regime in place at UK airports is necessary because of the level of security threat and is kept under constant review. We have no intention of compromising security levels nor do we anticipate changing our requirements in the next seven days," a spokesman for the department said.
Ryanair chief executive Michael O'Leary
"The Department for Transport directs aviation security measures under the Aviation Security Act 1982 not the Transport Act 2000 as Ryanair mistakenly seem to believe."
Ryanair has described the security measures as nonsensical and ineffective, and it accused the British government of giving extremists a public relations victory. It has asked that passenger body searches be scaled back from the current one in two to the normal one in four, which it says will still allow any suspect flights or suspect passengers to be individually body searched.
"The best way to defeat terrorists and extremists is for ordinary people to continue to live their lives as normal. Because of the additional security restrictions imposed by the Government last Thursday, the shambles at the London airports has been anything but normal," said Ryanair chief executive Michael O'Leary.
Ryanair has also criticised the security procedures that it says allow briefcases to be taken on board but prevent normal size carry-on luggage being taken on to aircraft as hand luggage.
In a separate statement, the airline pointed out that if liquids and cosmetics posed such a security threat to aircraft, the same restrictions should apply to the London Underground and Eurotunnel.
