US President Donald Trump has invited British Prime Minister Boris Johnson to visit him in the White House in the new year, British media reported on Sunday.

The Sunday Times newspaper reported that Trump's invitation to Johnson was made after the British prime minister's recent election win. Formal discussions on the exact timing of Johnson's visit are yet to held, the newspaper reported, citing Downing Street sources.

"Some potential dates have been floated in mid-January but nothing has yet been formally agreed. But it is clear that both sides want to make it happen sometime in early 2020," the Times quoted a source close to the White House as saying.

Johnson is reluctant to make the visit before delivering Brexit on Jan. 31 and prefers to go after a cabinet reshuffle scheduled in February in which he is expected to appoint cabinet office minister Michael Gove as his new trade negotiator, The Mail on Sunday reported.

Such an arrangement could let Johnson take Gove with him ahead of the talks of a post-Brexit trade deal with the United States, according to the report.

The development comes as Johnson won approval for his Brexit deal in the British parliament on Friday, the first step towards fulfilling his election pledge to deliver Britain's departure from the European Union by Jan. 31.

The parliamentary approval followed Johnson's landslide election victory earlier this month.

As Britain prepares to leave the bloc, Johnson and Trump agreed in a phone call on Monday to pursue an "ambitious" UK-US free trade agreement.

After Johnson's election win, Trump had said Britain and the United States were now free to strike a "massive" new trade deal after Brexit.

"This deal has the potential to be far bigger and more lucrative than any deal that could be made with the EU", Trump had said in a tweet earlier this month.

The White House did not immediately respond to a request for comment on the reported invite to Johnson.