Boris Johnson says he has spoken with president-elect Joe Biden and congratulated him on his election victory.
The prime minister said in a tweet: “I look forward to strengthening the partnership between our countries and to working with him on our shared priorities – from tackling climate change, to promoting democracy and building back better from the pandemic.”
The call took place at around 4pm and lasted approximately 25 minutes.
Downing Street said in a statement that Mr Johnson had “warmly congratulated” Mr Biden on his victory and “also conveyed his congratulations to vice president-elect Kamala Harris on her historic achievement”.
Ms Harris is the first female vice president, as well as the first woman of African-American and South Asian-American descent to get the job.
A Number 10 spokesperson added: “They discussed the close and longstanding relationship between our countries and committed to building on this partnership in the years ahead, in areas such as trade and security – including through NATO.
“The prime minister and president-elect also looked forward to working closely together on their shared priorities, from tackling climate change, to promoting democracy, and building back better from the coronavirus pandemic.
“The prime minister invited the president-elect to attend the COP26 climate change summit that the UK is hosting in Glasgow next year.
“They also looked forward to seeing each other in person, including when the UK hosts the G7 Summit in 2021.”
In the wake of Mr Biden’s triumph over Donald Trump there have been suggestions, dismissed by ministers and Downing Street, that the relationship between Mr Johnson and Mr Biden will not be as close as the one the PM enjoyed with Mr Trump.
The president has been a vocal supporter of both Mr Johnson and Brexit, while Mr Biden has been far more lukewarm.
He has been critical of the UK’s plans to override parts of the Brexit divorce agreement in relation to Northern Ireland if no trade deal is reached with the EU.
Mr Biden, who has Irish heritage, warned in the run-up to the US election about the Good Friday Agreement becoming a “casualty” of Brexit.
The call comes after it was revealed that Mr Johnson’s initial message of congratulations to the president-elect retained traces of Mr Trump’s name.
On Saturday, the PM offered his congratulations to Mr Biden and Ms Harris in a message on his Twitter account.
Boris Johnson’s message of congratulations to Joe Biden
The hidden words include a reference to ‘Trump’
Zooming in and altering the brightness and contrast of the image reveals the outlines of previous words
However, it has since been spotted that altering the brightness and contrast of the graphic attached to the tweet reveals the outline of what appears to be a previous statement.
Above the word “Biden” the word “Trump” can be seen, while the outlines of other words can also be found.
A government spokesperson said: “As you’d expect, two statements were prepared in advance for the outcome of this closely-contested election.
“A technical error meant that parts of the alternative message were embedded in the background of the graphic.”
Mr Trump has still yet to concede defeat in the US presidential election and has repeatedly claimed to have “won” the election.
He has also made unsubstantiated claims of fraud in the election process.