An Austrian defence ministry spokesperson added that sanitary and medical issues are still to be solved as well, and that it is not "unusual" that important international peace missions like this one be delayed, writes AFP newsagency.

The 3,700-strong EU force was initially planned to arrive in Chad in the end of October or beginning of November.

It is to be charged with protecting civilians, humanitarian workers and the UN mission in Chad and the Central African Republic, which is facing an influx of refugees from the conflict-torn Darfur region in eastern Sudan.

Besides the technical issues, internal EU divisions have also been delaying the mission.

France has been the most active defendant of EU deployment, saying the French contingent in Chad – a former French colony – would have 1,500 soldiers, to be added to the French military personnel already on the spot.

Ireland also approved on Wednesday (28 November) sending 400 troops to Chad which would make it the second largest contributor to the mission.

Other contributing countries include Poland, the Netherlands, Austria.

But some, notably the UK, have "offered to give political support, and where appropriate any technical advice", but stopped short of "any promises to offer any money or forces", UK European minister Jim Murphy said earlier this month.

London is already heavily involved in Iraq and Afghanistan and insists that it is "for the French and others to do the heavy lifting" in Chad.

The planned force still lacks ten helicopters, a third medical facility and other support assets, French General Henri Bentegeat, head of the EU's Military Committee, said earlier this month according to Reuters.

In the end, the issue may be left for EU leaders to tackle during their meeting in Brussels on 14 December.

"Ambitions have not been matched by resources (…) The concern now is that it could have to go to the summit and that wouldn't look very good for EU credibility", an EU diplomat told Reuters.