Donald Trump's comments calling for a ban on Muslims entering the United States makes him "unfit" to be President, Boris Johnson has said.
The Mayor of London went further than fellow Tories David Cameron and George Osborne in condemning his remarks on Wednesday, saying the Republican presidential candidate's remarks revealed a "stupefying ignorance".
However Mr Johnson did not go as far as to join those calling for Mr Trump to be banned from the United Kingdom, despite a petition attracting more than 220,000 signatures.
He echoed Mr Osborne in rejecting the idea of blocking him from the UK, saying his views must be beaten through democratic debate.
“I would invite him to come and see the whole of London and take him round the city, except I wouldn’t want to expose any Londoners to any unnecessary risk of meeting Donald Trump," Mr Johnson said.
Mr Trump shocked the world on Monday when he issued a statement calling for a "complete shutdown" of Muslim immigration to the US and later he said the ban should remain in place until authorities "can figure out" Muslim attitudes to the US.
Defending his comments later, he claimed parts of Paris and London were "no-go areas" for police because of large Muslim communities, a comment that enraged Mr Johnson.
Mr Johnson, who is among the favourites to succeed David Cameron as Prime Minister and could be in charge at Number 10 at the same time as Mr Trump might be in the White House, said: "I think Donald Trump is clearly out of his mind if he thinks that's a sensible way to proceed, to ban people going to the United States in that way, or to any country.
"What he's doing is playing the game of the terrorists and those who seek to divide us. That's exactly the kind of reaction they hope to produce.
"When Donald Trump says there are parts of London that are ‘no go’ areas, I think he’s betraying a quite stupefying ignorance that makes him frankly unfit to hold the office of President of the United States."
Register for free to continue reading
Registration is a free and easy way to support our truly independent journalism
By registering, you will also enjoy limited access to Premium articles, exclusive newsletters, commenting, and virtual events with our leading journalists
Already have an account? sign in
Join our new commenting forum
Join thought-provoking conversations, follow other Independent readers and see their replies