By Patrick Worsnip

UNITED NATIONS, June 30 (Reuters) - Alain Le Roy, a French diplomat with extensive experience in the Balkans, was named on Monday as new head of the U.N. peacekeeping department, one of the most high-profile jobs in the world body.

Le Roy, 55, will replace Jean-Marie Guehenno, also of France, who announced in March that he would step down after eight years running the ever-expanding department deploying the blue-hatted U.N. troops.

Le Roy worked at first as a petroleum engineer for French energy company Total before becoming a civil servant and holding posts for both the French government and the United Nations.

His U.N. jobs have included deputy special coordinator for Sarajevo, Bosnia, and regional administrator in Kosovo. Later he was European Union special representative in Macedonia and French ambassador to Mauritania. His most recent job is ambassador in charge of the Union for the Mediterranean Initiative, a project promoted by President Nicolas Sarkozy.

Le Roy takes over his new job at a time when diplomats say U.N. peacekeeping is under more strain than ever before. Its most challenging deployment is one the United Nations began this year along with the African Union in the violence-torn western Sudanese region of Darfur.

If fully deployed as planned by next year, it will consist of 26,000 troops and police, the largest such mission in the world. But only some 9,000 troops are currently in place and every detail of the operation has been marked by disputes between the United Nations and Khartoum.

Guehenno held the post longer than any of his predecessors and saw the number of U.N. troops around the world grow from some 50,000 to more than 100,000 and the peacekeeping budget from $2.5 billion to $7.5 billion. New missions were sent to Liberia, Ivory Coast, Haiti, Sudan and East Timor.

U.N. officials say that under him, peacekeeping changed from merely placing U.N. troops between armies that had stopped fighting to sending them into messy continuing conflicts like those in Darfur or the Democratic Republic of Congo.

Another challenge that Guehenno grappled with, and will also face Le Roy, is persistent allegations that U.N. peacekeepers have engaged in sexual exploitation and illicit trading in Haiti, Liberia, Congo and elsewhere.

Guehenno has been the most visible French national within the U.N. structure and France, a permanent Security Council member, had been widely expected to keep the job. (Editing by Bill Trott)

AlertNet news is provided by