He is best known as the architect of the Dayton peace accords which ended the war in Bosnia in 1995, and for which he was nominated for a Nobel peace prize.

Because of his reputation of confronting the warring leaders in the Balkans to get them to the negotiating table, Mr Holbrooke is called "the Bulldozer" or sometimes "Raging Bull" in the region.

Mr Holbrooke, 57, was born in New York and is of German-Jewish decent. He was educated at Brown University, and is married to the writer, Kati Marton.

War zone veteran

His first assignment for the state department was in Vietnam during the Indo-China wars. He later headed the State Department's European and Asian bureaux.

He has served as a former ambassador to Germany, and an assistant secretary of state for European affairs. In that post, he went to Bosnia as part of a peace-seeking delegation.

Since Dayton, he has been working in the private sector on issues in the Balkans, and part-time for the State Department mediating in the dispute between Greece and Turkey over the Mediterranean island of Cyprus.

In 1998 President Bill Clinton nominated Mr Holbrooke as the next US ambassador to the United Nations.

Getting along with Milosevic

Over the course of their various protracted and often difficult negotiations, Mr Holbrooke has established something of a rapport with the Yugoslav President, Slobodan Milosevic. The two men are said to be on a first name basis.

On a first name basis

There are stories of Mr Holbrooke sipping a mid-morning pear brandy with Mr Milosevic at Dayton, and the Yugoslav President once hosted the US diplomat for an 11-hour dinner near Belgrade at the former hunting lodge of the long-time Yugoslav President Tito.

The two men went for long walks in the woods around the time of the late-summer 1995 Nato airstrikes in Bosnia, which Mr Holbrooke heartily endorsed even as Mr Milosevic tried to soften up the native New Yorker, saying he loved the smell of coffee in Manhattan.

Mr Holbrooke says he has no moral qualms about "negotiating with people who do immoral things".

"If you can prevent the deaths of people still alive, you're not doing a disservice to those already killed by trying to do so," he said this summer after he failed to persuade Mr Milosevic to stop his military assault on ethnic Albanians in Kosovo.

"And so I make no apologies for negotiating with Milosevic and even worse people, provided one doesn't lose one's point of view."

Mr Holbrooke with Secretary of State Madeleine Albright

Mr Holbrooke is praised as one of the best and toughest US diplomats. But he is also known to have enemies in the US government.

In 1997, he was widely tipped to become secretary of state, but lost out to Madeleine Albright.

His nomination to become US ambassador to the United Nations was placed on hold, after he was accused of violating ethics laws governing the lobbying of former colleagues by ex-government officials.