Martti Ahtisaari, the former President of Finland, won the Nobel Peace Prize yesterday for his work as an intermediary in conflicts including Northern Ireland, Kosovo and southern Africa.

The Norwegian Nobel Committee cited Mr Ahtisaari’s “important efforts, on several continents and over more than three decades, to resolve international conflicts”. Ole Danbolt Mjoes, the head of the committee, said: “These efforts have contributed to a more peaceful world and to ‘fraternity between nations’ in Alfred Nobel’s spirit.”

Mr Ahtisaari, 71, who has been mentioned before as a potential laureate, said that he had not been expecting to win. “But definitely I was hoping, because this is the highest recognition that a person in my profession can have,” he said yesterday.

“I think it’s very rewarding to be in the same category as some people I have admired, like Nelson Mandela,” he added in reference to the 1993 winner. The committee rewarded a career devoted to diplomacy and conflict resolution from which Mr Ahtisaari’s six years as head of state were something of a distraction. While his decades of conflict resolution were full of “special cases”, he said that the highlight had been his tour as United Nations special envoy to Namibia, during which he helped to guide the country to peaceful independence. “Of course Namibia is the most important since it took so long,” he said.

However, many regard his greatest achievement as the brokering of the 2005 peace agreement that brought an end to the long-running war between the Indonesian Army and separatist guerrillas in the Indonesian province of Aceh. Previous mediators had failed but, with no experience in Asia, Mr Ahtisaari achieved a lasting peace in only seven months, in the aftermath of the Indian Ocean tsunami.

He was less successful in the former Yugoslavia, where he attempted to forge an agreement on the future of Kosovo with its former ruler, Serbia. As Finnish President, he had presented a joint Russian-EU peace proposal for a UN administration in Kosovo, which was accepted by the Serb Government.

After he was appointed UN special envoy in 2005, he lost the trust of the Serbs, who regarded him as pro-Kosovar. Russia subsequently blocked the proposal that he presented to the UN Security Council for “supervised independence” for the territory, and Kosovo declared independence in February this year.

Mr Ahtisaari was born in 1937 in Vyborg, in what is now Russia, and worked as a teacher before joining the Finnish Foreign Ministry. At the age of 36 he was sent to Africa, where he served simultaneously as Ambassador to Tanzania, Zambia, Somalia and Mozambique. He later became Finland’s Ambassador to the UN. In 1977 he became UN Commissioner for Namibia, which was then occupied by the apartheid Government of South Africa. In 1989 he headed the negotiations that led eventually to Namibia’s independence.

In 1994 he accepted the candidacy of Finland’s Social Democratic Party for the country’s first direct presidential elections, which he won narrowly. He travelled widely while in office and his tubby, bespectacled form, limping slightly from rheumatism, was affectionately regarded at home. But he often gave the impression of being constrained by domestic politics and he did not seek reelection in 2000.

Instead he founded the Crisis Management Initiative, based in Helsinki, as a vehicle for analysis and advocacy in international disputes.

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