The US President tweeted: “Theresa @theresamay, don’t focus on me, focus on the destructive Radical Islamic Terrorism that is taking place within the United Kingdom. We are doing just fine!”
Mr Trump appeared to have tagged the wrong user in his message, however. He later re-posted the tweet, tagging @theresa_may instead.
The Prime Minister earlier said the billionaire was “wrong” to have retweeted messages by Britain First’s deputy leader that featured misleading, Islamophobic videos.
Her spokesman added: “British people overwhelmingly reject the prejudiced rhetoric of the far right which is the antithesis of the values that this country represents – decency, tolerance and respect.”
Ms May has since faced pressure to cancel his state visit over the incident.
Mr Trump caused international upset and confusion on Wednesday when he retweeted three unverified videos that had been posted by Jayda Fransen, of Britain First.
One carried the caption, “Muslim migrants beating up a Dutch boy on crutches”, while another claimed to show an “Islamist mob” pushing a teenager off a roof and beating him to death and a third allegedly showed a Muslim man destroying a Virgin Mary statue.
The first was swiftly debunked by Dutch officials, but all three had been designed to stir up anti-Muslim sentiment online.
UK Communities Secretary Sajid Javid said Mr Trump had “endorsed the views of a vile, hate-filled racist organisation that hates me and people like me”, and was “wrong” to have done so.
Ms Fransen quickly moved to capitalise on the attention Mr Trump had brought her, saying she was “delighted”.
The spat is embarrassing for Ms May, who has pursued a close relationship with the Trump White House.
She has courted the new President and hopes to strike a trade deal with the US following Brexit – a key feature of her visit to Washington earlier this year.
The PM was the first world leader to visit Mr Trump after his inauguration and had hoped to shore up the so-called “special relationship”.
Following Mr Trump’s attack Carrie Symonds, director of communications for the Conservative Party, tweeted: “Wrong twitter handle. And that’s just the start.”
Ms May was far from alone in having condemned Mr Trump’s retweets, with faith groups on both sides of the Atlantic weighing in.
The Council on American-Islamic Relations said the President was ”clearly telling members of his base that they should hate Islam and Muslims”, while the Muslim Council of Britain called it “the clearest endorsement yet from the US President of the far-right”.
Justin Welby, the Archbishop of Canterbury, said Mr Trump’s decision to retweet the videos was “deeply disturbing”.
The White House Press Secretary attempted to defend the President by saying journalists were focusing on “the wrong thing”.
Sarah Huckabee Sanders said: “Whether it’s a real video, the threat is real. His goal is to promote strong border security and strong national security.”
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