(CNN) New York Rep. Chris Collins on Monday criticized Mitt Romney, a possible Secretary of State nominee in the new administration, calling him a "self-serving egomaniac."

"What do I know about Mitt Romney? I know that he's a self-serving egomaniac who puts himself first, who has a chip on his shoulder, and thinks that he should be president of the United States," Collins, a Donald Trump backer, told host Chris Cuomo on "New Day."

"There's no love lost between me and Mitt Romney," Collins added.

The New York Republican -- the first member of the House of Representatives to endorse Trump during the primary -- said he respects the president's prerogative but wouldn't select Romney if it were up to him.

"I'm going to leave it up to President-elect Trump to pick the people in his Cabinet that he thinks can serve in his administration," Collins said. "Would I choose him? No. But if President-elect Trump does, I will certainly support that decision."

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