Hédi Annabi, who has died aged 65 in the collapse of the United Nations headquarters in Port-au-Prince, following Haiti's earthquake, was the head of the UN mission in that country since 2007. Annabi was committed to the international interest. He was one of those UN personnel who have cut – or, at the very least, frozen – any identification with the national interests of their own country. They commit themselves to working solely towards the goals set by the decision-making authorities – the general assembly (GA), the security council (SC) and, within severely circumscribed limits, the secretary general (SG). Annabi's formidable intellect and political experience were deployed towards the aims set by numerous GA and SC resolutions in political and peacekeeping missions across the world.
A Tunisian, Annabi studied political science at the Institut d'Etudes Politiques, in Paris, English language and literature at Tunis University, Tunisia, and international relations at the Graduate Institute of International Studies in Geneva. After some years in the Tunisian foreign service and advising Tunisia's prime minister, he moved to the UN in 1981. He joined the UN team mediating the tensions in south-east Asia, whose work led to the establishment of a UN mission in Cambodia in 1991. In 1992 he joined the newly established Department of Peacekeeping Operations (DPKO) overseeing several missions in Africa. These included the ill-fated operation in Rwanda, for whose failure DPKO was blamed, while the SC – which established the mandate, determined the resources and had oversight responsibilities for the mission – escaped censure. In 1997 Kofi Annan named Annabi the deputy of DPKO, supervising all peacekeeping missions. In 2007 Ban Ki-moon
appointed him special representative and head of the UN stabilisation mission in Haiti (Minustah), from where Annabi planned to retire.
Annabi's abilities emanated from his sharp mind, which enabled him to master the complexities of vastly differing field missions, many with mandates that had to be interpreted and implemented on the ground, in harsh and often dangerous conditions. He reported on specific operations and their challenges to the SC, where he became a favourite for his crisp presentations – although they were often laced with barbs for its members for their lapses, in particular for western governments which enthusiastically supported new operations but balked at dispatching their own troops. His impressive memory meant he could respond precisely – at times drolly – to queries. Despite setbacks on the ground, he shunned discouragement.
In appearance, he was an unlikely-looking peacekeeper, far from the image of the big, brawny trooper in a blue beret or helmet (armed essentially for self-defence). Slight, short and balding with round glasses, he resembled a schoolteacher unsure of finding his way out. He lived up to his nickname, "headmaster", mentoring his juniors in managing operations. But in his peacekeeping tasks he was fully in control of all DPKO missions, reporting to the head of DPKO. He was known for working for 12 to 14 hours every day, while he then tended to his seriously ill wife, Danièle, at home. Yet he maintained regular phone contact with heads of mission in the field. His office, which had a large map of the world with pins at mission locations, was full of piles of papers (he could always find the one needed), behind which he hunched over his desk, a beige cardigan hanging loosely from his shoulders or chair.
He enjoyed the loyalty of his teams, who did not shirk from the long hours demanded by urgent events in widely dispersed time zones, despite his weakness for promoting the careers of select proteges. He was a DPKO champion in the unending war with the Department of Political Affairs, often chiding former team-mates who had moved to the SG's office for siding with the enemy.
By no means was he a dry and humourless bureaucrat; his irreverent wit drew regular laughter from his colleagues. He and his assistant, Lily, lovingly insulted each other while coping with the unending flow of cables, emails and phone calls throughout the day, and often at night. A group of female staffers – "Hédi's harem" – cajoled him into lunching with them every other month. On one occasion, he received an irate complaint from a Middle Eastern capital that a legal officer (from the same region) on a mission there was dressing inappropriately. Is she doing her job, he demanded. Phone me if she is not.
Annabi's death inevitably brings to mind that of Sérgio Vieira de Mello, the head of the UN mission in Iraq, who was killed in an explosion at the UN building in Baghdad in 2003. The loss of such luminaries diminishes the UN and the people it strives to serve, for Annabi was, in UN parlance, "as blue as can be" – unreservedly dedicated to the organisation and its sky-blue flag.
He is survived by Danièle and an adopted son.
• Hédi Annabi, diplomat, born 4 September 1944; died circa 12 January 2010
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