Sir Peter Ricketts, the prime minister's national security advisor, is the civil servant overseeing the process.

BBC: Q&A: Strategic defence and security review

Earlier the Iranian Ambassador met at the Foreign Office with the FCO's top civil servant and permanent under secretary, Peter Ricketts, to discuss the situation.

BBC: Iran issues warning over UK yacht crew

Up to 40 separate studies of defence expenditure are close to completion, which will be submitted to the NSC's small secretariat, led by the new national security adviser, Sir Peter Ricketts, a former head of the Foreign Office.

ECONOMIST: The future of British defence

As if to stress that it is stronger than ever, British government sources say a new joint US-UK National Security Strategy Board is to be set up headed by Sir Peter Ricketts, the prime minister's national security adviser and Tom Donilon, his White House counterpart.

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