Mitt Romney, the only Republican senator to cross the aisle and convict Donald Trump on the first charge of abuse of power during his impeachment trial, has said that the American President is "guilty of an appalling abuse of public trust".
In an emotional speech on the Senate floor, the 72-year-old lawmaker from Utah, spoke of his own faith and of the possibility for retribution from the ruling Republican Party he may face over his decision to go against Trump in one of the two charges against the president.
"I'm aware that there are people in my party and in my own state who will strenuously disapprove of my decision and in some quarters I will be vehemently denounced.
"I'm sure to hear abuse from the President and his supporters," Romney, the Republican Party's nominee for President of the United States in the 2012 election, said.
He then went on to ask, "Does anyone seriously believe that I would consent to these consequences other than from an inescapable conviction that my oath before God demanded it of me?"
"I take an oath before God as enormously consequential. I knew from the outset that being tasked with judging the President -- the leader of my own party -- would be the most difficult decision I have ever faced. I was not wrong," he said.
"Mr. Romney's defection, which he announced a couple of hours before the final vote, was a stark reflection of the sweeping transformation of the Republican Party over the past eight years into one that is now dominated almost entirely by Mr. Trump. And it deprived the president of the monolithic Republican support he had eagerly anticipated," The New York Times noted.
On Wednesday, the Republican Party-driven Senate voted that Trump has been found not guilty in his impeachment trial, ending a bid to remove him from office.
The Senate voted to acquit him 52-48 on charges of abuse of power and 53-47 on obstruction of Congress.
Democrats charged Trump in December with pressuring Ukraine to smear former US Vice President Joe Biden, a potential 2020 White House rival from the Opposition Democratic Party.
Going against his own party, Romney voted to convict the President on the abuse of power charge brought by the House in the impeachment trial. He, however, voted to acquit Trump on the second article, obstruction of Congress.
"The grave question the Constitution tasks senators to answer is whether the President committed an act so extreme and egregious that it rises to the level of a high crime and misdemeanor," Romney said. "Yes, he did."
"The President asked a foreign government to investigate his political rival. The President withheld vital military funds from that government to press it to do so. The President delayed funds for an American ally at war with Russian invaders," he said.
"The President's purpose was personal and political. Accordingly, the President is guilty of an appalling abuse of public trust," Romney said, justifying his decision to vote against Trump.
President Trump was quick to attack Romney and called the senator a "Democrat secret asset."
If convicted on either charge, Trump would have had to turn over his office to Vice-President Mike Pence.
The Democratic-led House of Representatives approved the articles of impeachment on December 18.