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In his opening monologue Wednesday, Sean Hannity warned President-elect Donald Trump to be cautious as he meets with dozens of prospective cabinet nominees and other national leaders as Inauguration Day approaches.

Today, he met with Mayor Rahm Emanuel (D-Chicago), President Obama's former chief of staff and a proponent of sanctuary cities, former Vice President Al Gore (D-Tenn.), a fierce advocate for climate issues, and he continues to vet former Gov. Mitt Romney (R-Mass.) for secretary of state.

"Remember all of the nasty things Romney said on the campaign trail," Hannity said, addressing Trump.

Romney has called Trump "phony", a "fraud", and said "dishonesty is Donald Trump's hallmark".

Hannity said that, while Trump likely understands the ideologies of the people with which he meets, he must tread carefully in Washington as these folks may too be the first to oppose him, should they find disagreement with his administration.

"The political class will turn on him on a dime," he said.

Former Speaker of the House Newt Gingrich (R-Ga.) reacted to Hannity's remarks.

What do you think? Let us know in the comments below.

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