Donald Trump has given his biggest endorsement yet to Roy Moore as the Republican establishment rallied around the Senate candidate accused of child sex assault, ahead of a crunch vote.

The US president tweeted that “we need Republican Roy Moore to win in Alabama” with a week to go before voting for the Senate seat.

Mitch McConnell, the Republican leader in the Senate, also rowed back on past criticism by saying “the people of Alabama” should decide the race.

Mr Moore, the firebrand Republican candidate, has faced numerous accounts of inappropriate sexual contact with teenage girls, some as young as 14.

He has denied all the claims and said he is victim of a “witch hunt”.