Theresa May is facing renewed calls to cancel a state visit for Donald Trump over his response to deadly unrest in Virginia.
MPs urged the PM to rescind her invitation after Mr Trump would not condemn white supremacist groups outright for violence that left a woman dead.
During ill-tempered exchanges with reporters at Trump Tower on Tuesday the president said "there is blame on both sides".
The comments appeared to equate the actions of the far-right demonstrators with those protesting against them, provoking criticism from both Republicans and Democrats.
In the UK a number of Labour MPs called for Mrs May's offer of a visit with state honours for Mr Trump to be torn up.
Shadow defence secretary Nia Griffith tweeted: "A state visit by #DonaldTrump would shame this country and betray all we stand for. Theresa May should revoke the invitation immediately."
Nottingham South MP Lilian Greenwood said Mr Trump's comments were "sickening" and a "new low".
"When will UK Govt admit he should never had been invited for a state visit?" she wrote on Twitter.
Referring to a visa questionnaire given to tourists visiting America, MP for Rhondda Chris Bryant said: "May cd rescue smidgen of moral authority now by rescinding Trump invite. After all US immigration ask 'are u or have u ever been a Nazi?'"
Violence erupted in Charlottesville, Virginia, on Saturday after a group of far-right extremists gathered to protest a decision to remove a statue of a Confederate general.
Heather Heyer, 32, later died when a car was driven into crowds as anti-fascist demonstrators clashed with the white supremacists.
Mr Trump faced heavy criticism in the immediate wake of the unrest after he said there was blame on "many sides".
He took two days to condemn the actions of the far-right groups in particular, eventually branding the KKK, neo-Nazis and white supremacists as "repugnant to everything that we hold dear as Americans" in a statement on Monday.
Made additional remarks on Charlottesville and realize once again that the #Fake News Media will never be satisfied...truly bad people!— Donald J. Trump (@realDonaldTrump) August 14, 2017
However, during a boisterous press conference at his Manhattan residence on Tuesday the president appeared to have reverted to his previous position.
He acknowledged there were "some very bad people" among the statue protesters, but added: "You also had people that were very fine people, on both sides".
In the hours after the comments the hashtag #ImpeachTrump trended worldwide on Twitter, while Labour MPs criticised the president over his renewed stance.
Shadow education secretary Angela Rayner wrote: "Millions of Americans died fighting the Nazis in WW2, my husband's dad fought alongside them with so many others, POTUS has brought such shame."
Birmingham Yardley MP Jess Phillips tweeted: "This should be the end, but it won't be, it will get worse, violence will ramp up, people will die and everyone else will be to blame #Trump"
Mrs May has faced repeated criticism over her decision to offer a state visit to her US counterpart shortly after he took office.
However the controversial occasion was reportedly put on hold after Mr Trump grew concerned that he would be greeted by protests on arrival.
Number 10 sources said at the time that no date had been fixed, but officials were believed to be looking at 2018.