London's new Muslim mayor, Sadiq Khan, slammed Donald Trump as "ignorant" after the presumptive Republican nominee suggested the mayor would be exempted from his proposal to temporarily ban Muslims from entering the United States.

And now this has become a tale of two cities -- Paris Mayor Anne Hildago hopped the train to London to congratulate its new mayor. What did she think of Donald Trump's proposal to ban all Muslims? Not much.

"Mr. Trump is just stupid, my God,"she said.

Khan won the London election for mayor by the biggest margin any mayor has ever had, despite his faith and his history as a political activist and human rights lawyer, which forced him to battle off claims that he was sympathetic to some extremist views.

And now that Khan is the mayor of one of the great Western capitals, Donald Trump was inevitably asked if he would be banned, like all the rest of the world's Muslims.

"There will always be exceptions," Trump told the New York Times. Sadiq Khan has now told Trump what to do with his exceptions.

"I think Donald Trump has ignorant views about Islam. It's not just about me, I don't want to be the exception to be allowed to go to America," Khan said. "You can be a Muslim, and you can be European. You can be a Parisian mayor and a London mayor and work closely together. And I hope Donald Trump looks to the lessons that London sent last Thursday and recognizes that it's possible to be Western and Muslim and to be friends with mayors of Paris as well."

Kahn said this goes beyond the personal - that the Trump ban on Muslims is fodder for the extremists and reinforces their view that the West is their enemy and that there is no place for them there.

Kahn also said that if it is a Donald Trump-Hillary Clinton showdown, he not only hopes she wins, but also that she "trounces him."