Eliza Collins

USA TODAY

Who is smarter: Donald Trump or the mayor of London?

On Monday, Trump appeared on Good Morning Britain where he talked about criticism he’s received from Sadiq Khan, who was recently elected London’s first Muslim mayor and has frequently criticized Trump.

“He’s been quite critical of you as you know. He’s attacked you for being ignorant,” Piers Morgan said to Trump.

“Let’s do an IQ test,” Trump interrupted, before saying that he was offended by what Khan had said (including his hope that Trump loses the election) and he wouldn’t forget.

“When he won, I wished him well. Now I don’t care about him,” Trump said.

“I’m not at war. I just think it’s very rude of him,” Trump responded when Morgan said Trump was “at war” with Khan.

When Morgan asked Trump for a response to British Prime Minister David Cameron saying that Trump's proposal to temporarily ban Muslims from entering the United States as "stupid" and "divisive."

"Looks like we're not going to have a very good relationship," Trump responded. "Who knows, I hope to have a good relationship with him but it sounds like he's not willing to address the problem either."

"Would you like him to withdraw the particular comments that you're stupid, divisive and wrong with your view about those things?" Morgan asked.

"I'm not stupid OK? I can tell you that right now. " Trump said. " I don't think I'm a divisive person, I'm a unifier"