"They discussed the fruitful negotiations between their respective negotiators on a British-American agreement and agreed to continue at the same pace during the week", Downing Street announces.
The President of the USA and the Prime Minister of the United Kingdom also agreed to talk to each other in the coming days.
Trump has previously tried to lure the British with a "fantastic" agreement that would help the United Kingdom avoid, or at least mitigate, an economic blow when the USA introduces trade tariffs on Wednesday.
Since the United Kingdom left the EU, several prime ministers have tried to reach an agreement with the USA, but none have been closer than Starmer is said to be now.
In contrast to the EU, the British have refrained from retaliatory tariffs on American goods. The country is believed to want to reach an agreement before Wednesday, April 2, which Trump calls "Freedom Day".