Sir David Manning was one of four top diplomats giving evidence to Lords committee who highlighted major changes in ‘special relationship’

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Something seismic has changed in the US-British relationship that will require the UK to look elsewhere for allies and accept that deals such as cooperation over the British nuclear deterrent are now in question, a former British ambassador to Washington has warned.

Sir David Manning, told a Lords select committee on international relations that something fundamental was happening to the special relationship and the change was not a blip.