Donald Trump has appeared to concede the US election for the first time, saying that president-elect Joe Biden "won".

He made the admission in a tweet along with more unfounded claims the vote was unfairly and deliberately stacked against him.

"NO VOTE WATCHERS OR OBSERVERS allowed, vote tabulated by a radical left privately owned company, Dominion, with a bad reputation & bum equipment that couldn't even qualify for Texas (which I won by a lot!), the Fake & Silent Media, & more!"

It is a significant acknowledgement from Mr Trump, who, despite losing the Electoral College by 74 and popular vote by 5 million, has refused to follow tradition and accept the result.

Last week he became the first president since 1992 to fail to get re-elected, following projections Mr. Biden had successfully swung the key states of Pennsylvania, Arizona and Georgia to win the White House.

Since then, the Republican incumbent has launched legal challenges and tried to undermine the validity of the result - but failed to produce any significant evidence of the mass ballot stuffing and voter fraud he is alleging.

World leaders and former presidents - including George H.W Bush - have all treated the contest as finished, and sent their messages of congratulations to Mr. Biden.

Prime Minister Boris Johnson is among those to already be treating the former vice-president as the winner and a change of administration in January as inevitable.

In the run up to his and vice president-elect Kamala Harris' inauguration on 20 January, Mr Biden has set up a transition team so he can hit the ground running when they formally take office.

And he has appointed a team of scientists to advise him on tackling the Coronavirus pandemic - one of his top priorities, he said in his victory speech.

The US has had the highest number of cases and deaths in the world of coronavirus - 10,906,000 and 245,000 respectively, according to Johns Hopkins University.

Mr. Trump has been criticised by some for his actions during the pandemic - which resulted in him catching the disease in September.

Dr. Anthony Fauci, one of the president's top advisers, warned recently the US "could not possibly be positioned more poorly" as it heads into winter.