President Trump and Rep. Mark Sanford. (Photos: Shawn Thew, Richard Ellis/Pool via Getty)

Rep. Mark Sanford, R-S.C., said President Trump threatened to run a primary challenger against him in 2018 if he voted against the Republicans’ proposed replacement for Obamacare.

In an interview with the Charleston, S.C., Post and Courier, Sanford said that Mick Mulvaney, the director of the White House Office of Management and Budget, told him, “‘The president asked me to look you square in the eyes and to say that he hoped that you voted ‘no’ on this bill so he could run (a primary challenger) against you in 2018.’”

The American Health Care Act, orchestrated by House Speaker Paul Ryan, was abruptly withdrawn Friday after it became clear that it lacked sufficient support to pass. The ultraconservative House Freedom Caucus, of which Sanford is a member, led the charge from the right to oppose the bill, and Trump has publicly blamed its members for the bill’s failure.

Sanford said he counts Mulvaney as a friend and that it was clear he was delivering the message reluctantly and on Trump’s behalf, rather than of his own volition.

The veteran congressman was surprised by the strong-arm tactic, telling the Post and Courier, “I’ve never had anyone, over my time in politics, put it to me as directly as that.”

Still, “I have nothing against Donald Trump,” Sanford insisted. “There is zero personal animosity from me towards him. I try to shoot it right down the middle, as I have always done in politics. … I want to help him succeed, because if he succeeds, the Republican Congress, and our country by extension, succeeds.”

A spokesperson for Sanford did not immediately respond to a request for comment.