Nicholas Burns, the top American official negotiating to tighten UN sanctions against Iran, is to stand down, the US Secretary of State, Condoleezza Rice, announced yesterday.

Mr Burns, a former US Ambassador to Nato and Greece as well as a former State Department spokesman, has played a significant role in negotiating the two UN Security Council resolutions imposing sanctions against Iran over its nuclear programme.

The foreign ministers of Germany and the five permanent members of the Security Council – Britain, China, France, Russia and the United States – will meet in Berlin on Tuesday to discuss a third sanctions resolution.

The US believes that Iran aims to acquire nuclear weapons and the UN sanctions are designed to force Tehran to suspend its uranium enrichment activities, which can produce fuel for nuclear weapons or nuclear power plants.

Mr Burns, 51, has also been the lead US negotiator on an agreement that would give India access to American nuclear fuel and equipment for the first time in 30 years even though it has tested nuclear weapons and refused to join nonproliferation agreements.

Mr Burns’ likely replacement is William Burns, an experienced diplomat who has been Ambassador to Russia since 2005.

In 2005 he served temporarily as Undersecretary of State for Political Affairs, the job that he would now take up if nominated by President Bush and confirmed by the US Senate. (Reuters)

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