UK security adviser attended US-Iran talks and judged deal was within reach

Exclusive: Jonathan Powell thought Tehran’s ‘surprising’ offer on its nuclear programme could prevent rush to war, sources say

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Britain’s national security adviser, Jonathan Powell, attended the final talks between the US and Iran and judged that the offer made by Tehran on its nuclear programme was significant enough to prevent a rush to war, the Guardian can reveal.

Powell thought progress had been made in Geneva and that the deal proposed by Iran was “surprising”, according to sources.