In conciliatory speech, president-elect vows to rebuild infrastructure and aims to double economic growth

US president-elect Donald Trump said on Wednesday he would bind the nation's deep wounds and be a president "for all Americans", as he praised his defeated rival Hillary Clinton for her years of public service.

Riding a wave of euphoria from his supporters at a victory party in his home city of New York, Trump sought to bury the divisions and rancor that had made the 18-month presidential campaign so toxic.

"For those who have chosen not to support me in the past, of which there were a few people, I'm reaching out to you for your guidance and your help so that we can work together and unify our great country," Trump said, during his speech proclaiming a stunning victory in the White House race.

"I pledge to every citizen of our land that I will be president for all Americans."

In his victory speech, he also said he had a great economic plan, would embark on a project to rebuild US infrastructure and would double US economic growth.

His win raises a host of questions for the United States at home and abroad. He campaigned on a pledge to take the country on a more isolationist, protectionist "America First" path. He has vowed to impose a 35 percent tariff on goods exported to the US by US companies that went abroad.

He was also noticeably conciliatory toward his vanquished rival, whom he has spent months berating as a corrupt favorite of the Washington establishment who broke the law by using a private server to send and receive classified data.

"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," he said.

"I mean that very sincerely."

The provocative billionaire president-elect, 70, said Clinton telephoned him to concede the race shortly after the state of Pennsylvania, which has voted Democratic in presidential races since 1992, was slotted into his win column.

"She congratulated us - it is about us - on our victory, and I congratulated her and her family on a very, very hard-fought campaign," he said.

The real estate mogul also pledged to "deal fairly with everyone," including "all other nations."

"We will get along with all other nations willing to get along with us. We will have great relationships," he added.

"While the campaign is over, our work on this movement is now really just beginning," Trump said, in a nod to the grassroots anti-establishment, anti-Washington ground swell that upended the race with historic results.

"We're going to get to work immediately for the American people, and we're going to be doing a job that, hopefully, you will be so proud of your president."

Democratic President Barack Obama, who campaigned hard against Trump, telephoned the Republican "to congratulate him on his victory" and invited him to the White House for a meeting on Thursday, the White House said in a statement on Wednesday. Obama will make a statement later on Wednesday about the election, the White House said.

"Ensuring a smooth transition of power is one of the top priorities the President identified at the beginning of the year and a meeting with the President-elect is the next step," the White House said.