David Bamford BBC News at the UN in New York

When the United Nations weapons inspectors move into Iraq, they will be led by a 72-year-old former foreign minister of Sweden, Hans Blix.

Dr Blix took over the post held by Australian Richard Butler, who headed the UN inspection team that went into Iraq following the Gulf War until its forced withdrawal four years ago.

In the short time Dr Blix has been head of the UN Monitoring, Verification and Inspection Commission, or UNMOVIC, he has won respect from all sides.

He comes across to the Iraqis as honest, straightforward and fair - and to the Americans as serious, assertive and a man who means business.

Diplomatic tightrope

Dr Blix shows little indication of being even slightly affected by the pressure he must be under.

The inspectors ended their last Iraq mission in 1998

Yet when he moves into Iraq in the next few weeks, his judgement and the manner in which he carries out his job may be the difference between war and peace.

Despite his insistence that it is the United Nations Security Council that must judge whether or not Iraq is guilty of materially breaching its UN commitments, it is Dr Blix's perceptions on the ground that will determine the framework.

United States President George W Bush was delighted when Dr Blix went on record as saying the Iraqis needed to know that any failure to cooperate with his weapons inspectors would entail a reaction from the Security Council.

Nevertheless, Dr Blix has been careful not to endorse the military option specifically and has not shied away from describing some of the American proposals as technically unworkable.

He has also said consistently that he believes the Iraqi officials he meets are genuine in wanting to find a peaceful way out of this crisis, while steering clear of characterising the motives of their leader, Saddam Hussein.