President Obama also criticized Donald Trump's 3 a.m. Twitter rants: "He may be up at 3 a.m., but it's because he's tweeting insults"

President Barack Obama tore into Donald Trump in a speech in Cleveland on Friday, saying he’s “embarrassing us on the world’s stage” and mocking the GOP nominee’s claims that he will fight for working people if elected.

“I want to say to him, look, if a guy spent 70 years on this earth showing no regard for working people — there’s no record that he’s supported minimum wage or supported collective bargaining, or invested in poor communities, and then suddenly he’s going to be the champion of working people? Come on. Come on, man!” Obama said.

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“Apparently in a speech yesterday he started talking about ‘global elites,’ that there was a conspiracy of ‘global elites,’ ” Obama continued. “This is a guy who spent all his time hanging around, trying to convince everybody he was a global elite, talking about how great his buildings are, how luxurious, and how rich he is and flying around everywhere, and all he had time for was celebrities. And now suddenly he’s acting like he’s a populist out there. ‘Man, I’m going to fight for working people.’ ”

“Come on, man,” Obama scoffed again to cheers. “You want to know what somebody’s going to do? Look what they’ve been doing their whole lives.”

The president also said Trump lacks the knowledge and temperament to be president, and alluded to his 3 a.m. Twitter rant attacking former Miss Universe Alicia Machado.

“He may be up at 3 a.m., but it’s because he’s tweeting insults,” the president said.

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Obama also criticized Trump’s 2005 hot-mic tape that showed him making lewd comments about women — which the GOP candidate dismissed as “locker room talk” — and applauded the emotional speech First Lady Michelle Obama made on the topic on Thursday.

“I could not be prouder of her,” he said, adding, “Yes, she was sticking up for women. Yes, she was thinking about the lessons we’re teaching the next generation. But she was also talking on behalf of men who know that we’re better than this.”

The president also criticized Republicans for failing to condemn Trump and his treatment of women before the 2005 tape emerged last week.