Former U.S. Vice President Mike Pence said he will not support Donald Trump in the 2024 election.

Pence said in an interview with Fox News on Friday, for the first time since the former U.S. president became the presumed Republican candidate: "It’s not surprising that I will not support Donald Trump this year."

Pence competed against Trump for their party’s nomination but withdrew from his attempt before the voting began last year.

This decision makes Pence the latest in a series of senior officials in the Trump administration who refused to endorse their former leader’s attempt to return to the Oval Office, and while Republican members of Congress and other Republican party officials have largely rallied behind Trump, a outspoken minority has continued to oppose his attempt.

It also marks the end of a transformation for Pence, who had long been regarded as one of Trump’s most loyal defenders, but broke away from his running mate twice by refusing to approve Trump’s unconstitutional scheme to stay in power after losing the 2020 election. When Trump supporters stormed the Capitol building on January 6, 2021, in an attempt to block the certification of Joe Biden’s victory, Pence had to flee to the Senate loading dock while rioters outside chanted: "Hang Mike Pence!"

To participate in the Republican primary debates, Pence was required to sign a pledge stating he would support the party’s final candidate. During the first debate in Milwaukee, Pence was among the candidates who raised their hands when asked if they would support Trump even if he were convicted on one of the four criminal indictments against him.

But Pence made it clear that he has serious reservations about Trump’s behavior and political positions.

He said during his campaign launch speech: "I believe anyone who places themselves above the Constitution should never be President of the United States, and anyone who asks someone else to place them above the Constitution should never be President of the United States again."

As the campaign progressed, he sounded the alarm about the party’s resistance to sending aid to Ukraine, and called on his fellow Republicans to reject what he called the "populist siren song" embraced by Trump and his followers.

In an interview with Fox, Pence said he is "very proud" of his record and Trump’s record in office, but said: "During my presidential campaign, I made it clear there are deep differences between me and President Trump on a range of issues, not just our disagreement over my constitutional duties exercised on January 6."

"I mean, when I saw his candidacy, I saw him move away from our national commitment. I saw him begin to shy away from the sanctity of human life," also referring to what he called "Trump’s retreat from toughness on China and support for our administration’s efforts to enforce" the ban on popular goods like TikTok."

“In each of these cases, Donald Trump seeks and articulates an agenda that conflicts with the conservative agenda we judged during our four years. That is why I cannot in good conscience support Donald Trump in this campaign.”

Pence refused to disclose who he would vote for, saying: "I will keep my vote to myself," but he made clear it would not be Biden.

He said: “I will never vote for Joe Biden. I am a Republican.”