In an interview with The Atlantic, Sen. Mitt Romney Willard (Mitt) Mitt RomneyThe Memo: Warning signs flash for Trump on debates GOP votes to authorize subpoenas, depositions in Obama-era probe Overnight Defense: Trump hosts Israel, UAE, Bahrain for historic signing l Air Force reveals it secretly built and flew new fighter jet l Coronavirus creates delay in Pentagon research for alternative to 'forever chemicals' MORE (R-Utah) opened up about his decision to vote to convict President Trump Donald John TrumpBarr criticizes DOJ in speech declaring all agency power 'is invested in the attorney general' Military leaders asked about using heat ray on protesters outside White House: report Powell warns failure to reach COVID-19 deal could 'scar and damage' economy MORE of abuse of power Wednesday evening.

The Republican senator said it was "the most difficult decision" of his life. On the floor of the Senate Wednesday, the former GOP presidential nominee emotionally told the chamber that Trump was "guilty of an appalling abuse of public trust," a sentiment he echoed in his Atlantic interview.

"The president did in fact pressure a foreign government to corrupt our election process," Romney told the publication. "And really, corrupting an election process in a democratic republic is about as abusive and egregious an act against the Constitution—and one's oath—that I can imagine. It's what autocrats do."

Romney was also one of two Senate Republicans to vote for additional witnesses in the Senate impeachment trial last week, along with Sen. Susan Collins (Maine).

On the other article of impeachment — obstruction of Congress — Romney said he would vote to acquit the president.