Keir Starmer and Donald Trump spoke on Sunday and had "productive" talks towards a UK-US trade deal, the British Prime Minister's Downing Street office said on Sunday.

Since Britain's exit from the European Union at the start of the decade, successive UK governments have sought to strike a trade deal with the United States.

"They discussed the productive negotiations between their respective teams on a UK-US economic prosperity deal, agreeing that these will continue at pace this week," a statement read.

"They agreed to stay in touch in the coming days."

Trump himself has dangled the prospect of a "great" deal that could help the United Kingdom avoid, or at least soften, the blow caused by the tariffs the US president has promised.

Unlike the EU, Britain has declined to retaliate against the tariffs already imposed on the country's steel industry.

Though the previous Conservative government did not manage to ink a deal in, Labour party leader Starmer came away from a Washington visit in late February hopeful of reaching an agreement.

The UK is believed to want a trade deal ahead of Trump's so-called April 2 "Liberation Day", when he is set to unveil a range of tariffs for different trading partners.

But any such accord is yet to see the light of day. (AFP)