Story highlights "The guy declared bankruptcy four times. Is this the guy we're putting forward?," Sayegh asked.

When Trump became the Republican nominee, Sayegh was a vocal supporter of Trump.

(CNN) The man Donald Trump appointed this week to a prominent public affairs role at the Treasury Department harshly criticized him during the Republican presidential primary.

Republican consultant Tony Sayegh will serve as assistant secretary of public affairs at the Treasury Department under Steven Mnuchin. In his role as a Fox News contributor in 2015 an early 2016, Sayegh described Trump as "the poster child for crony capitalism" and pointed to Trump's multiple bankruptcies.

Past criticism of Trump has reportedly played a role in disqualifying some prospective members of his administration. Bloomberg reported this week that some of Mnuchin's picks in the Treasury Department are facing push back for their past comments about the President.

When Trump became the Republican nominee, Sayegh was a vocal supporter of Trump, telling Fox Business in August 2016, "I believe we need to begin to evolve into a more populist party to reflect the will of the people, not just the will of the elites of our party. And that is exactly why Donald Trump will prevail."

But in the months of the heated primary campaign, Sayegh questioned whether Trump was the candidate Republicans wanted to put forward.

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