Kamala Harris has called Donald Trump to concede defeat in the US presidential election.
A senior adviser to the vice president said she talked about "the importance of a peaceful transfer of power" and "being a president for all Americans".
Ms Harris is due to deliver a concession speech at 4pm local (9pm UK time).
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President Joe Biden also called Mr Trump to congratulate him on his election win and invited him to the White House for a transition meeting.
"President Biden expressed his commitment to ensuring a smooth transition and emphasized the importance of working to bring the country together," the White House said.
Mr Biden phoned Ms Harris too to congratulate her on her "historic campaign".
Mr Trump won a decisive victory - comfortably clearing the 270 electoral votes needed to clinch the presidency.
He said he had won "an unprecedented and powerful mandate".
Declaring victory earlier in Palm Beach, Florida, Mr Trump told his supporters: "We're going to help our country heal.
"We have a country that needs help, and it needs help very badly. We're going to fix our borders. We're going to fix everything about our country and we've made history for a reason tonight."
He doubled down on his promise to crack down on illegal immigration and promised a "golden age of America".
He added: "This is a magnificent victory for the American people that will allow us to 'make America great again'."
The president-elect briefly paused his speech as the crowd chanted "USA, USA, USA!".
After the Republican Party also took control of the Senate from the Democrats, Mr Trump said: "America has given us an unprecedented and powerful mandate. We have taken back control of the Senate. Wow.
"Wow. That's great."
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Mr Trump picked up his first battleground state of the night after he was declared the winner of North Carolina.
Around an hour later, he was declared the victor in Georgia, taking the state he narrowly lost to Mr Biden in 2020.
Shortly afterwards, he was projected as the winner of Pennsylvania, which was considered the most pivotal of the seven battleground states.
Mr Trump's return to the White House was confirmed after he won Wisconsin, pushing him over the 270 Electoral College votes needed to win the presidency.
Harris to oversee ceremonial certification of election
Ms Harris ran as the Democratic candidate for the White House after President Biden left the race amid concerns about his advanced age following his disastrous debate with Mr Trump in June.
As the vice president, she is expected to oversee the US Congress' ceremonial certification of the election.
It is unclear what role she will play in the future of the Democratic Party.
(c) Sky News 2024: Kamala Harris calls Donald Trump to concede defeat in US election