Donald Trump ensured he left the G7 summit in a state of chaos by announcing from Air Force One on Saturday night that the US had withdrawn its endorsement of a joint communiqué and launching a blistering attack on his host, Justin Trudeau, the Canadian prime minister.

Mr Trump described Mr Trudeau as dishonest and weak as he accused Canada of trying to take advantage of US interests.

He was already on his way to Singapore for next week's summit with Kim Jong-un when he fired off two tweets unravelling the progress made during the previous 24 hours.

It mirrored the build-up to talks which were thrown into disarray by his appeal for Russia to be readmitted to the G7 and promised not to back down on tariffs.

However, European officials believed they had secured a limited breakthrough by agreeing a form of words that could be released with American approval, despite obvious tensions.