Kamala Harris has said she is "proud" of her campaign in the US presidential election after losing to Donald Trump as she told supporters: "We must accept the result".
In a concession speech in Washington, the vice president said she "will engage in a peaceful transfer of power" and help Mr Trump and his team with the transition.
"While I concede this election, I do not concede the fight that fuelled this campaign," she added.
"I am so proud of the race we ran and the way we ran it."
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Ms Harris, who smiled and waved as she entered the stage, acknowledged her supporters were feeling a "range of emotions".
She told supporters "it's going to be okay," adding: "Sometimes the fight takes a while. That doesn't mean we won't win."
"Don't ever give up", she added. "Do not despair."
Ms Harris delivered her remarks at Howard University - which she used to attend - in the same spot where she hoped to give a victory speech.
She thanked President Joe Biden for his support - as well as her running mate Tim Walz, who was in the audience along with Nancy Pelosi, the former House of Representatives speaker.
Sky News' US correspondent Martha Kelner said she "could see some signs of emotion" on Ms Harris' face, "particularly halfway through this speech when the crowd burst into spontaneous chants of 'we love you'".
"I think I saw her get a little glassy-eyed."
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Harris discusses 'importance of peaceful transfer of power' with Trump
Earlier, Ms Harris called Mr Trump to concede defeat in the US presidential election.
A senior adviser to Ms Harris said she talked about "the importance of a peaceful transfer of power" and "being a president for all Americans".
Mr 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 also spoke to Ms Harris on the phone to congratulate her on her "historic campaign".
Former president Barack Obama issued a statement congratulating Mr Trump on his victory.
"This is obviously not the outcome we had hoped for," he said. "But living in a democracy is about recognising that our point of view won't always win out, and being willing to accept the peaceful transfer of power."
Trump claims 'unprecedented and powerful mandate'
Mr Trump won a decisive victory - comfortably clearing the 270 electoral college 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."
Mr Trump spoke of his promise to crack down on illegal immigration and vowed to bring 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."
Harris expected 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 tells supporters 'we must accept result' of US election after losing to Donald Trump