The two leaders reaffirmed their commitment to strengthening cooperation on a range of issues, including the negotiation of a U.S.-Britain free trade agreement, White House deputy press secretary Judd Deere said in a tweet.

Trump also congratulated Johnson on his electoral victory, Deere added.

Johnson was officially declared winner of Britain's general election on Friday when his Conservatives passed the finishing post for a majority government.

U.S. Vice President Mike Pence said during his visit in Britain in September this year that the United States "is ready, willing, and able to do a free trade agreement with the UK immediately upon the completion of Brexit."