Reporters travelling with Pence said he suddenly aborted his plans for a dinner and reception hosted by Peru's president and went back to his hotel, in time for Trump's televised address from Washington on the military action in response to a suspected poison gas attack in Syria.

The United States, France and Britain were all taking part in the strikes against Bashar al-Assad's Syrian regime.

The summit in Peru is a once-every-three-years meeting of leaders from across Latin America, the US and Canada.

Trump cancelled his trip to the summit on Tuesday, with the White House explaining that he had "to oversee the American response to Syria and to monitor developments around the world."