Working in parallel with Nato-led troops, Mr Kouchner will head the massive operation overseeing the return of refugees and re-establishing civilian infrastructure in Kosovo.

Bernard Kouchner was among the founders of the relief organisation Medecins sans Frontieres (Doctors without Borders) in the 1970s and was an outspoken proponent of humanitarian action during the Bosnian war.

"He has those qualities that the secretary-general said he was looking for: vision, ability to manage and knowledge of the region," said UN spokesman Fred Eckhard.

European shortlist

Mr Kouchner was chosen among a final list of four candidates that also included Italian European Commissioner Emma Bonino, the UK's retiring Liberal Democrat leader Paddy Ashdown and the Dutch Housing and Environment Minister, Jan Pronk.

Mr Kouchner: known as an outspoken critic of humanitarian objectives

Responsibility for the Kosovo team had been expected to go to a European as the European Union has assumed major financing responsibility for the reconstruction project.

At present, the post is being filled on a temporary basis by a senior UN official, Sergio Viera de Mello.

US diplomat James Covey, who has worked on Balkan issues for the White House and the UN, was appointed Mr Kouchner's deputy.

Humanitarian background

Named health minister after the Socialists returned to power in France in 1997, Bernard Kouchner has continued to grab the headlines with his high-profile aid work, and has been a frequent visitor to the Balkans.

He was among the first to articulate the concept of a "humanitarian right of intervention" overriding state sovereignty - a right invoked by Nato during the conflict in Kosovo.

The French doctor has a reputation as a publicity seeker.

He was criticised for posing on a Mogadishu beach carrying a sack of rice on his shoulder during the flawed UN humanitarian intervention in Somalia in 1992.

And he embarrassed the French Government in the early 1990s by branding the late President Mobutu Sese Seko of Zaire as a "walking bank safe in a leopard-skin hat" just as French troops were intervening to drive out anti-Mobutu rebels.

UN mission

The appointment of four deputies to head different components of the Kosovo mission was also announced on Friday.

France's Dominique Vian - currently the prefect of French Guayana - will handle civil administration, special Yugoslav envoy for the UN High Commissioner for Refugees Dennis McNamara will handle humanitarian affairs, and Daan Everts, the head of the OSCE mission to Kosovo, will head an office of institution building.