The US Senate has acquitted a defiant Donald Trump in his second impeachment trial in just over a year, after the Democrats failed once again to muster enough votes to convict the former president on a charge of inciting the deadly insurrection at the Capitol on January 6.

The Senate voted 57-43 on Saturday to convict Trump on a single impeachment count - incitement of insurrection. But that majority of all 50 Democrats in the upper chamber of the US Congress, joined by seven Republicans, fell 10 votes short of the 67 needed for a conviction, two-thirds of the 100-member Senate.