Airbus spokesman Florian Taitsch said the European Aviation Safety Agency (EASA) had ordered the inspections and follow-up checks late last year after unexplained cracks were discovered in the combustion chamber of an A400M engine owned by Malaysia.

No problems had been found in any of the other engines checked, which belong to the first 31 delivered A400M aircraft. "All the engines affected have been inspected and this is a unique incident," Taitsch said.

Facing heavy losses on its programme to supply up to 170 of the aircraft to seven European NATO members, Airbus on Wednesday took a fresh writedown of 1.2 billion euros (£1 billion) and urged the governments concerned not to fine it too heavily for technical snags and delays.

It cited "significant risks ahead" for Europe's biggest defence project, which sources said was originally valued at 20 billion euros but was now slated to cost well over 30 billion.

It was not immediately clear when the company and the NATO buyer nations - Belgium, France, Germany, Luxembourg, Spain, Turkey and Britain - would meet to discuss the programme.

The EASA airworthiness directive called for inspections of all engines similar to the Malaysian one, and follow-on checks after 500 hours, and then every 250 hours after that.

A spokesman for the German air force said minor cracks had been found in the 10 affected German A400M engines, but they were common in the combustion chambers and there was no impact on aircraft safety or operation.

(Reporting by Andrea Shalal; Editing by Mark Trevelyan and Michael Nienaber)