Donald Trump looked to win a crucial battleground in the race to become the next US president, narrowing Kamala Harris's road to the White House.

In North Carolina, one of the seven pivotal swing states where the contest is anticipated to be tight, the Republican candidate prevailed.

As voters cast their ballots, the election seemed close at first, but as expected returns from firmly red states like Florida, Texas, and Alabama came in throughout the night, Mr. Trump gained ground.

Support for Democratic candidate Ms. Harris came from the east and west coast bastions of her party, including California, Delaware, and New York.

The outcome of the contest will have a sweeping impact on global politics, including in the UK where Sir Keir Starmer’s Government may have to grapple with upheaval in America’s security and defence approach if Mr Trump wins.

Seven states are considered so-called swing states in this year’s election.

Georgia, Pennsylvania, Nevada, Arizona, Michigan and Wisconsin are the remaining six where Ms Harris now hopes she can win support on her path to win power.

If the voting results follow predictions by the Associated Press, Mr Trump will have gained 230 votes in the electoral college, and Ms Harris 209 with the current states which have been called.

Under the US voting system, a total of 270 votes in the college are needed to win the presidency.

The election has largely unfolded smoothly across the USA, despite some voters suffering delays in casting their ballots, and a spate of what the FBI described as non-credible bomb threats.

The economy – and reducing inflation – is a key issue for Americans according to exit polling, but other areas of concern for voters include immigration, protecting democracy and abortion rights.

As they take part in the presidential poll, 10 states across the US are also voting on whether to enshrine the right to abortion in law.

In Florida, efforts to amend the state’s constitution to add abortion rights failed, but New Yorkers voted in favour of a similar amendment.

Concerns about the future of American democracy have emerged largely as a result of Mr Trump attempts to overturn his loss in 2020, and the actions of his angry supporters in January 2021, who stormed Washington DC’s Capitol building.

Mr Trump said on Tuesday that he had no plans to tell his supporters to refrain from violence if Ms Harris wins because they “are not violent people”.

The UK Government has been working hard to win over Mr Trump in case he is re-elected, after a trans-Atlantic spat developed in recent weeks over Labour Party volunteers heading to the US to campaign for his rival.

Sir Keir is expected to be following the results of the US election, but his official spokesman did not say whether the Prime Minister would be staying up overnight to watch the results roll in.

Speaking to GB News from Florida, Reform UK leader Nigel Farage described Mr Trump’s lead in the race as “the most incredible political comeback in any of our lifetimes”.

Mr Farage, who has fostered close links with the Trump campaign, added: “He was down and out in 2020, he has been through the courts, he has been through goodness knows what and here he is just a few hours away from becoming the 47th president of the USA.”

The Republican candidate would likely chart a new US course on major conflicts in Ukraine and the Middle East, areas where Sir Keir has largely followed the lead of US President Joe Biden.

Former Conservative prime minister Boris Johnson has voiced concerns about what the result might mean for global affairs, telling Channel 4 News: “The thing that really worries me right now is Ukraine and the future of democracy in that country.

“I think there is a risk whatever happens in this election that there will be a disaster in Ukraine.”

In central London, Democrat supporters went virtually silent as a television network showed Mr Trump ahead in swing states.

Some held their head in their hands as concern spread about Ms Harris’ prospects, and there were shouts of “No, that can’t be right” as projections on CNN showed Mr Trump strongly ahead among Latino voters in Michigan.

A spokesperson for Republicans Abroad has meanwhile claimed Democrats are on course for a “shellacking” and their path to victory is “getting narrower and narrower”.

Sara Elliot also told Times Radio: “It is definitely not what we expected in some ways, being that the polls were as close as they are.”