Former House Speaker Newt Gingrich (R-Ga.) said on "Fox & Friends" that President Trump must become "substantially more disciplined" if he wants to accomplish his agenda.

Gingrich said the latest mistake by the president was getting into a heated back-and-forth with reporters over the Charlottesville white supremacist riots.

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"The president was inadequate initially, particularly when he began to say there some good people in the crowd of neo-Nazis and alt-right. If you're a good person and you see someone chanting anti-Semitic chants and you see somebody wearing a Nazi flag, you leave, you don't stay," Gingrich said, adding Republicans must "condemn unequivocally the kind of violence, bigotry and racism we saw in Charlottesville."

But he said violent left-wing protesters also deserve condemnation, noting the ACLU called out violence from both sides.

Gingrich said Trump had seemingly put to rest the controversy over his response one day earlier with a clear condemnation of white supremacists, but then went off-course on Tuesday in a news conference at Trump Tower.

"In 1997, Donald Trump wrote "The Art of the Comeback." I think he should take a couple of days here in August and reread his own book. He's much more isolated than he thinks he is," said Gingrich, adding Trump's support among Congress is weak right now.

He said members of Congress don't know what to expect day to day from President Trump, who sent out a series of tweets early this morning, blasting Republican senators Lindsey Graham and Jeff Flake.

Watch the interview above.

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