ReutersSir Keir Starmer and Donald Trump have agreed that "productive negotiations" about an economic deal between the UK and US will "continue at pace", Downing Street has said.
The Sunday night phone call between pair comes after sources at No 10 said the government was prepared to retaliate against US tariffs if needed.
Trump has imposed a series of tariffs targeting goods from other countries in the first few months of his second stint in the White House, but British negotiators are trying to win a last-minute exemption ahead of a looming deadline.
A 25% tax on car imports is expected to come in on Wednesday, with threats of wider tariffs also being imposed.
The two leaders also discussed keeping up "the collective pressure on Putin" over Ukraine, Downing Street's spokesperson said.
No 10 also said Trump began the call by sending King Charles III his best wishes, after the monarch experienced temporary side effects during cancer treatment earlier in the week.
