"The election is over" and it is time to put aside the partisanship and the rhetoric designed to demonise one another, US President-elect Joe Biden said on Tuesday.
Biden's Twitter statement came hours after incumbent President Donald Trump, a Republican, finally agreed that the presidential transition process should start, after weeks of wrangling.
The General Services Administration (GSA), the federal agency overseeing the handover, said it was now acknowledging Biden, a Democrat, as the "apparent winner" of the November 3 election.
"The election is over. It's time to put aside the partisanship and the rhetoric designed to demonise one another. We have to come together," Biden tweeted, commenting on one of the most divisive presidential elections in American history.
"I pledge to be a president who seeks not to divide, but to unify. Who doesn't see red and blue states, but a United States," the 78-year-old tweeted on Monday.
"And who will work with all my heart to win the confidence of the whole people," he wrote.
Meanwhile, President Trump, 74, continues to allege massive voter fraud without providing evidence, and his legal challenges have so far proved fruitless.
Trump said on Monday that the GSA must "do what needs to be done", but still refuses to concede the election, repeating unsubstantiated claims of a "rigged election".
The move grants the Democrat access to millions of dollars in funds, as well as access to national security briefings and government officials, so he can properly prepare to take over the presidency on January 20.