David Cameron thinks Donald Trump's call for all Muslims to be banned from the United States as "divisive, unhelpful and quite simply wrong", Downing Street has said.
The Prime Minister's official spokeswoman said politicians should "look at ways they can bring communities together" when questioned by The Huffington Post UK at the daily briefing of Lobby journalists.
The Republican presidential candidate faced calls to be banned from entering the UK after he said there should be a "total and complete shutdown of Muslims entering the United States" in the wake of Paris and California terror attacks.
But Mr Cameron's official spokeswoman said: “The PM completely disagrees with the comments made by Donald Trump which are divisive, unhelpful and quite simply wrong.
"The PM is clear that as we look at how we tackle extremism and this poisonous ideology, what politicians need to do is look at ways they can bring communities together and make clear these terrorists are not representative of Islam, indeed what they are doing is a perversion of Islam.”
Mr Cameron, by contrast, yesterday praised the unknown bystander who shouted "you aint no Muslim, bruv" at the alleged perpetrator of the Leytonstone underground tube attack, which left a 56-year-old with serious injuries.
The PM said: "Some of us have dedicated speeches, media appearances and sound bites, and everything to this subject but 'You ain't no Muslim, bruv' says it all much better than I ever could."
As to whether the property mogul and politician should be banned from entering the country, the PM's spokeswoman said: “That’s a hypothetical. With the first primary six weeks away, I should think his views will be fixed on winning over the views of the American people at the moment.”
Sunder Katwala, the director of the British Future think-tank which focuses on immigration, said on Tuesday that Home Secretary Theresa May should consider blocking any attempt by Mr Trump to visit Britain in response.
The businessman owns a golf course in north Scotland and was a frequent visitor to the British isles when trying to persuade local residents of the benefits of the controversial scheme.
Donald Trump arrives for the opening of The Trump International Golf Links Course in 2012 in Balmedie, Scotland
"Donald Trump’s call for a blanket ban on Muslims visiting America represents a real low in electoral politics. It is hugely irresponsible for a prominent figure like Trump to fan the flames of prejudice in this way," Mr Katwala said in a statement.
"The UK Home Office has set out clear guidelines which have led to the exclusion of preachers of hate from the UK if their presence here would not be conducive to the public good.
"Theresa May has excluded extreme Islamists on these grounds, and also kept out those who have fanned extreme anti-Muslim prejudice, such as the bloggers Pamela Geller and Robert Spencer. Trump’s statements are more extreme than theirs."
He added: "Unless and until Trump were to retract these highly prejudiced comments, there is a good case for making clear that he would be refused entry to the UK by the home secretary."
In a statement posted on Twitter, Trump said: "Without looking at the various polling data, it is obvious to anybody the hatred is beyond comprehension. Where this hatred comes from and why we will have to determine.
"Until we are able to determine and understand this problem and the dangerous threat it poses, our country cannot be the victims of horrendous attacks by people that believe only in Jihad, and have no sense of reason or respect for human life. If I win the election for President, we are going to Make America Great Again."
Mr Katwala, said Trump's proposals were "ludicrous and unconstitutional" as well as a "gift to Isis propaganda, playing into the idea of a 'clash of civilisations'".
"It is important that the UK government makes very clear that this extreme view is rejected and repudiated in the strongest possible terms," he said.
"It would ban well over a million British citizens from visiting the US simply because of their faith background, including our business secretary Sajid Javid and our Olympic hero Mo Farah, among countless others people in business, academia, politics, sports, science and civic society."
It is not the first anti-Muslim statement Trump has made in his quest to secure the Republican nomination for president. He has previously claimed to have watched footage of American Muslims cheering after the September 11 attacks on New York, despite no TV station being able to find any such film.
Yvette Cooper, Labour's former shadow home secretary and leadership candidate, condemned Trump's comment as "ignorant and islamophobic".