Mr Jaafari, 57, whose Dawa party struggled with Saddam for decades, attracted 64 votes in the United Iraqi Alliance ballot, just one vote ahead of his closest rival, Vice-President Adel Abdel Mahdi. His re-appointment is due to be formally confirmed by a three-member presidential council selected by the 275-member assembly when it sits in the next fortnight.

Regarded as a religious Shia Muslim with a close relationship to Iran, he has so far lacked the influence to persuade insurgents, the majority of them Sunnis, to abandon their armed resistance. He has had more success coaxing disaffected Sunni political parties back into the political arena.

Mr Jaafari was born in the Shia shrine city of Kerbala and attended university in the northern city of Mosul. He joined Dawa in 1966. The party did not fully embrace armed resistance until the 1980s, when Mr Jaafari fled to Iran, before moving to London in 1989. His five children live in Britain.

He returned to Iraq after Saddam was toppled and, with a reputation as a subtle negotiator, was found by a poll to be Iraq’s most highly regarded politician in 2003, while a member of the US-appointed Governing Council.

As Prime Minister he angered the Sunni minority by visiting Iran, describing the relationship between the two former enemies as “very friendly and strong, and expanding”. The Kurds also lost patience with him, accusing him of monopolising control and reneging on agreements that he had made to recruit their support before taking office.

Keen to promote himself as a unifying figure, Mr Jaafari has consistently promised to bridge Iraq’s bitter sectarian divides with dialogue and diplomacy, a pledge that he renewed yesterday. “The Iraqi process is as big as Iraq, so it is the duty of all Iraqis to build the new Iraqi house,” he said. “This process will . . . move ahead on the security situation, on services, on the economic situation and reconstruction, on political performance internally and externally.”

US and British officials have long privately complained of his inability to make decisions quickly, and his penchant for lengthy sessions of consultation with political partners and Shia religious figures such as Grand Ayatollah Ali al-Sistani in Najaf.

Mr Jaafari won the nomination ahead of Abdel Mahdi, 63, a leading figure in the Shia Supreme Council of Islamic Revolution, who had been the favourite among diplomats because of his moderate outlook and ties with Washington.

As the vote was under way, the Iraqi capital was hit by a series of bombs that killed five people, including an 18-month-old girl. A suicide bomber killed two police commandos and a woman at a checkpoint in southern Baghdad, and in the north of the city two people died and twelve were wounded in a restaurant bombing.

The lack of security facing Mr Jaafari’s renewed premiership is the overriding concern of Iraqis, and one unlikely to find a quick solution in the light of the assembly election results, confirmed on Friday last week. Although Iraqis voted as a single nation, their ballots represented them in clearly defined divisions as Shias, Sunnis, Kurds, Turcomen or Christians. Secular parties were crushed, while those based on ethnic identity triumphed in 13 of 18 provinces. None of this is encouraging for the review of the Iraqi constitution, due to start after the new government and assembly have formally sat.

Shias, who have the majority in the new assembly, have stated that there can be no change to the charter envisaging a federal Iraq with regional autonomy. Sunnis want important amendments, fearful that a federalised Iraq would allow Shia and Kurds to exploit oil reserves, located largely outside Sunni areas.

Violence is likely to remain the principal manifestation of Iraq’s political process for a long time, and conclusive constitutional negotiations are unlikely in the near future in such a divided nation.

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