Hillary Clinton said the nation is “more deeply divided than we thought” during her concession speech in New York.
The Democrat said the result of the presidential election will be “painful” and it “will be for a long time”.
In her concession speech the morning after the election, Ms Clinton tried to reassure the long faces that greeted her at the midtown Manhattan venue.
Supporters at the Wyndham Hotel could be seen crying, their heads bowed, while others rubbed their eyes after a long night.
“This is painful and it will be for a long time but I want you to remember this,” she said. “Our campaign was never about one person or one election. It was about the country we love, about building a country that was hopeful, inclusive and big-hearted.”
“I still believe in America and I always will,” she added.
She urged Americans to look to the future and that Mr Trump is owed an “open mind” from the voters.
It was her first appearance since the election result, and just a few hours after hundreds of supporters had crowded into the nearby Javits centre, ready to welcome her as the first woman president in history.
“This loss hurts,” she said, addressing younger voters. “But please never stop believing that fighting for what is right is worth it. It is, it is worth it.
“And so we need you to keep up these fights now and for the rest of your lives. And to all the women and the young women who put their faith in me, nothing has made me prouder than to be your champion.
“Now, I know we have still not shattered that highest and hardest glass ceiling but some day, someone will and hopefully sooner than we think right now.
“And to all the little girls who are watching this, never doubt that you are valuable and powerful and deserving of every chance and opportunity in the world to pursue and achieve your own dreams.
“Finally, I am so grateful for our country and for all it has given to me. I count my blessings ever single day that I am an American and I still believe as deeply as I ever have, that if we stand together and work together, in our differences, have conviction in our strengths and our love for this nation, our best days are still ahead of us.
“Because you know I believe we are stronger together and we will go forward together. And you should never, ever regret fighting for that.”
The event was delayed by an hour as the Clinton campaign were reportedly scrambling to set up an event which they had not expected to hold. When her top aide, Huma Abedin, walked in, followed by her running mate Tim Kaine, the audience stood and clapped.
“I’m proud of Hillary Clinton as she is a history-maker in everything she has done,” said Mr Kaine.
“Her people were so deeply loyal to her as she was deeply loyal to them,” he said.
Ms Clinton got 218 electoral votes, while Mr Trump swept to victory with 276 votes, gaining control of key battleground states like Ohio, Pennsylvania, Michigan, North Carolina and Florida.
Ms Clinton’s campaign chair, John Podesta, came alone to the iconic Javits Centre on Tuesday evening, urging supporters not to give up yet. Ms Clinton stayed at a nearby hotel with her entourage as the final votes trickled in.
“She's done an amazing job, and she's not done yet,” he said.
The Democrat had struck ahead with the popular vote, with a lead of 167,661 votes. But it was not enough to win the White House.
Ms Clinton’s supporters showed emotion, anger and amazement as they left the Javits centre in the early hours of Wednesday morning without a glimpse of their leader.
At his “victory party” in midtown New York, Mr Trump thanked his allies and said he had received a phone call from his rival to congratulate him after an 18-month-long campaign.
"I've just received a call from Secretary Clinton. She congratulated us ... on our victory, and I congratulated her and her family on a very, very hard-fought campaign,” he told the crowd.
“I mean, she fought very hard. Hillary has worked very long and very hard over a long period of time, and we owe her a major debt of gratitude for her service to our country.”
At the Wyndham Hotel, Ms Clinton ended with: “Let us have faith in each other. Let us not grow weary or lose heart, for there are more seasons to come and more work to do.”Reuse content