Airbus' long-delayed A400M military transport will make its first test flight during the week beginning December 7, "weather permitting", the European planemaker said Friday.

The A400M was to replace ageing military cargo carriers in several European air forces but its development has been dogged by a series of serious technical problems and its in service date has been pushed from 2009 to 2013.

Some governments have begun to tire of waiting for Airbus to resolve the issues, and French and German officials have given the firm until the end of the year to prove that the project remains viable.

"Ground tests of the first A400M are progressing satisfactorily at our facility. This allows us to anticipate a first flight in the week 50, weather permitting," said Airbus military chairman and managing director Domingo Urena.

When the 20-billion-euro (28-billion-dollar) A400M project began it was hoped that a first test flight would be held in 2008 and that air forces would have had the airframe in service by the end of this year.

There is now little hope that the first production models will be delivered by 2012 and none is expected on the world's battlefield airstrips until 2013.

The delays have cost millions and forced Airbus to renegotiate its contracts with several customers. South Africa has dropped its order entirely and Britain has mulled switching is business to US manufacturers.

Seven European countries -- Belgium, Britain, France, Germany, Luxembourg, Spain and Turkey -- have ordered 180 planes between them, in most cases to replace ageing Transall and C130 Hercules transports.