An American diplomat is to be appointed to the UN’s top political post in a controversial move that will align the world organisation more closely with Washington, The Times has learnt.

Lynn Pascoe, the US Ambassador in Indonesia, is the leading contender to take over as under Secretary-General for Political Affairs — a job that Britain also wanted.

The appointment is certain to provoke fear among other UN member states that Washington will have too much power in the organisation.

The UN’s political chief is responsible for mediation efforts in sensitive hotspots such as Iraq, Lebanon, Sudan and the Palestinian territories, where an American will find it hard to distance himself from official US policy.

The American appointee also will rule over an expanded political arm that is expected to incorporate the UN’s disarmament department and the new peacebuilding support unit.

Mr Pascoe, 63, a Mandarin-speaking career diplomat, is expected to be named in the coming days as Ban Ki Moon, the new Secretary-General, attempts a difficult balancing act in assembling his team for his five-year term.

In his early appointments, the former South Korean Foreign Minister has tried to place officials from key developing nations in top posts, naming a deputy Secretary-General from Tanzania, a chief of staff from India, and a management chief from Mexico. But he risks losing the political capital he has earned by naming an American as his political supremo.

Britain wanted to regain control over the political affairs department, held for seven years by Sir Kieran Prendergast before Ibrahim Gambari of Nigeria took over in July 2005. It proposed Sir John Holmes, the British Ambassador in Paris. But Sir John, despite his lack of experience with relief work, was given the top humanitarian post instead.

The US, the UN’s largest financial contributor, has traditionally provided the head of the UN management department to run the bureaucracy. When Mr Ban was elected, Washington decided to seek control of the peacekeeping department because, with almost 100,000 “blue berets” around the world, it now accounts for the bulk of the UN budget.

But Mr Ban’s advisers argued that the US should get a top political job to bind it more closely to the world organisation.

• Asha-Rose Migiro, the newly appointed deputy Secretary-General, is not the first woman to hold the office (Report, January 6). That honour fell to Louise Fréchette.

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