Theresa May will visit Donald Trump in spring this year following preparatory December meetings between key staff from Downing Street and the United States president-elect's team, a Number 10 source said.
The Prime Minister's joint chiefs of staff Nick Timothy and Fiona Hill travelled to the US last month to build links with Mr Trump's team.
The mission was part of Mrs May's efforts to build a relationship with the controversial tycoon ahead of his inauguration on January 20.
The source said: "This was part of a process leading towards the PM's first visit with President-elect Trump.
"During the second phone call with president-elect Trump, the Prime Minister suggested it would be a good idea for key staff from both teams to meet. President-elect Trump agreed this would be useful.
"We are pleased to have been able to make that happen and the Prime Minister looks forward to visiting the new president in the spring."