Republican presidential candidate Donald Trump | Sean Rayford/Getty Images Donald Trump slams ‘radical’ Paris and London “The only reason I wouldn’t go to some parts of New York is the real risk of meeting Donald Trump,” responds London mayor.

Neighborhoods in Paris and London are so dangerous that police refuse to go there, Donald Trump said Tuesday as he defended his plan for a “total and complete shutdown of Muslims entering the United States.”

Despite a barrage of criticism for his comments on Muslims on Monday, Trump stuck to his guns, telling talk show hosts that he wanted to stop the U.S. having "radicalized" no-go areas like in European capitals.

"The real Paris is a different Paris than the City of Light that you read about," he told Good Morning America's George Stephanopoulos Tuesday.

"They have areas in Paris where it is so radicalized and so vicious ... that the police refuse to go there. They will not go there. That’s what’s going to happen with our country.”

He was no more polite about London, telling MSNBC's Morning Joe that "London and other places ... are so radicalized that the police are afraid for their own lives.”

A spokeswoman for British Prime Minister David Cameron said Tuesday that Trump's comments on Muslims were "divisive, unhelpful and quite simply wrong."

Boris Johnson, the mayor of London, went further, saying Trump's comments on the dangers of London were "ill-informed" and "utter nonsense."

He added that "the only reason I wouldn't go to some parts of New York is the real risk of meeting Donald Trump."

The Metropolitan Police — London's police force — was also critical of Trump, saying: "We would not normally dignify such comments with a response, however on this occasion we think it's important to state to Londoners that Mr. Trump could not be more wrong. Any candidate for the presidential election in the United States of America is welcome to receive a briefing from the Met Police on the reality of London policing."

Another well known Brit joined in the Trump bashing. Author J.K. Rowling tweeted that Trump was worse than Voldemort, the evil dark lord in her best-selling Harry Potter series.

How horrible. Voldemort was nowhere near as bad. https://t.co/hFO0XmOpPH — J.K. Rowling (@jk_rowling) December 8, 2015

But Trump was unrepentant, telling Joe Scarborough on Morning Joe on Tuesday that “we’re not talking about the Japanese internment camps, not at all, but we have to get our hands around a very serious problem,” referring to the World War II-era camps that Japanese Americans were placed in.

Trump proposed the “total and complete shutdown” of Muslims’ entry into the United States on Monday evening, hours before a campaign rally in South Carolina. His statement came in response to a shooting in San Bernardino, California, that killed 14 people.

Asked by Scarborough to flesh out his plan, Trump said that U.S. Customs and Border Protection agents would need to question people entering the country about their religion, and stop anyone who answered "Muslim."

When asked for his message to American Muslims, Trump said: “We love you. We want to work with you. We want you to turn in the bad ones.”

Criticism of Trump has not been confined to Europe. Rival Republican presidential candidate Jeb Bush called Trump "unhinged," Senator John McCain called him "foolish," and former vice president Dick Cheney said his comments go "against everything we stand for and believe in."

The Democratic mayor of St. Petersburg, Florida, said he was "hereby barring Donald Trump from entering St. Petersburg until we fully understand the dangerous threat posed by all Trumps."