The release of 15 British sailors and Marines from Iran is both the Prime Minister’s triumph and further evidence that Margaret Beckett lacks credibility as Foreign Secretary. On this occasion Tony Blair is indebted to his foreign policy adviser, Sir Nigel Sheinwald, who held secret talks with Ali Larijani, the Secretary of Iran’s Supreme National Security Council. The telephone call between the two men is regarded as the breakthrough encounter.

A diplomatic success for a seasoned career diplomat, then. But the curious thing about Sir Nigel is that for all his cool-headed skill and the experience accrued during a 31-year career, he is not noted for having a delicate touch.

Rather, those who have worked with him describe him as outspoken, abrasive and ambitious. Yet if this is all that he is, he would not have pulled off a succession of sensitive, clandestine missions involving visits to such cities as Damascus, Tripoli, Baghdad, Jerusalem, Ramallah and Khartoum. Most notably he was involved in the secret negotiations that resulted in Libya’s abandonment of its nuclear weapons programme in 2003.

He is certainly brusque, says one who knows him, and he is regarded with awe. Another says he is all right if you stand up to him; he is fun too, he can be indiscreet, and as the father of three sons he is a dedicated family man. A nanny once called him a pussycat, which might surprise those who have seen only the rottweiler, but which indicates that there is more to Sir Nigel than a fierce front — and we all know that being forceful and scary is a way of keeping people at a distance.

He sees himself as someone who asks the tough questions and has no time for prevarication. A Middle East analyst recalls that his first comment to him was: “Are you in fa-vour of suicide bombers?”

After an education at Harrow County School for Boys and Balliol, Oxford, he joined the Diplomatic Service in 1976. A Moscow posting ended suddenly after an accident in which a Russian was killed by the car he was driving. He has since worked in Washington, done two stints in Brussels, and a range of policy jobs in London, where he headed the Foreign Office news department from 1995 until 1998.

He served as spokesman for Douglas Hurd and Malcolm Rifkind, but the turning point of his career was the arrival of new Labour in 1997. He quickly established a good relationship with Robin Cook, then Foreign Secretary, though his job was not to represent his Foreign Office colleagues but to implement the Prime Minister’s views. At 53 his appointment as the next Ambassador to the US makes it clear that he is very much Blair’s man. Will he be Brown’s too? Certainly it is easy to imagine that they will understand each other.

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