The Senate majority leader has congratulated Joe Biden on becoming US president-elect – in a significant blow to Donald Trump.
Top Republican Mitch McConnell said the Electoral College – a group of people who voted to formally confirm the result of last month’s election – “had spoken”.
“Many of us had hoped the presidential election would yield a different result,” he admitted on Tuesday.
Joe Biden is due to be sworn in on 20 January
“But our system of government has the processes to determine who will be sworn in on 20 January.”
Mr McConnell described Democrat Mr Biden, who was vice president under Barack Obama and also a former senator himself, as someone “who has devoted himself to public service for many years”.
Kamala Harris will be the first woman vice-president of the US
He also congratulated vice president-elect Kamala Harris, saying “all Americans can take pride that our nation has a female vice president-elect for the very first time”.
Before those remarks, he poured praise on Mr Trump’s “endless” accomplishments during the last four years.
Donald Trump is still refusing to accept he lost the election
The admission marks a crucial abandonment by one of the most senior GOP figures of the incumbent president’s position, which is to refuse to accept the election result.
Mr Trump has claimed – without evidence that has stood up to legal scrutiny – that the vote was rigged against him.
Republican Senator Roy Blunt, the chairman of the inaugural committee, also said on Tuesday the panel will “deal with” Mr Biden “as the president-elect”.
Just last week, the Republicans on the same committee had declined to publicly do so.
Mr Trump will become the first one-term president since 1992 when he leaves the Oval Office next month.
He will be replaced by Mr Biden, after the Democrat challenger managed to flip key red states blue – like Arizona, Georgia and Nevada.
His gain of Pennsylvania four days after polls closed gave him enough Electoral College votes to put him past the halfway line, and he eventually collected 306 to Mr Trump’s 232.
Mr Biden’s inauguration ceremony will be very different from the usual ceremonies used to induct new presidents into office, given the coronavirus pandemic.
The committee organising it said they wanted to ensure it “honours and resembles sacred American traditions while keeping Americans safe and preventing the spread of COVID-19”.
“Vigorous health and safety protocols” will be followed and “the ceremony’s footprint will be extremely limited, and the parade that follows will be re-imagined”, they clarified.
US residents are also being urged not to travel to attend the ceremony at the Capitol in Washington DC and instead watch from home.