Trump: Something ‘mentally wrong’ with Weiner

“He's gotta drop out at some point, but perhaps he won't. He'll go through the process," he predicted.

Trump's comments come as Weiner tries to recover from the revelation that he had continued holding sexually explicit conversations with young women on the Internet months after similar behavior forced him from Congress.

Since Weiner's admission, recent polling has shown a steep drop in support for his bid to be New York mayor in a race he had previously led. And the candidate has faced calls from a number of Democrats urging him to stand down.

"He certainly — his polls are absolutely abysmal now. It's amazing. The second time was too much for the voters," Trump said. "I've known this guy for years; he's not a good guy."

"He's a very sick guy, and New York City does not need him," Trump added. 

Over the weekend, Danny Kedem, Weiner's campaign manager, resigned. But Weiner insisted he would stay in the race, telling reporters at an event on Sunday that he always expected a “tough campaign.”