President Donald Trump’s administration is filling one of the State Department’s top positions with a controversial conservative journalist who has promoted conspiracy theories related to the Jan. 6 attack on the Capitol and was fired as a speechwriter by the first Trump administration when it was revealed that he had spoken at a conference tied to White nationalists, sources familiar with the move told ABC News.

The sources said that the man, Darren Beattie, will now be the acting Under Secretary for Public Diplomacy and Public Affairs, a so-called “Top 10” position that, as the State Department’s website describes it, “leads America’s public diplomacy outreach, which includes messaging to counter terrorism and violent extremism.”

“The Under Secretary oversees the bureaus of Educational and Cultural Affairs and Global Public Affairs, and participates in foreign policy development,” the website adds.

Beattie is slated to start in the position on Monday, sources said. He was already serving in another senior role within the State Department, but the new move to such a high-level position has raised concerns among many of its employees, sources said.

More than two years ago, Beattie launched a right-wing media outlet called Revolver News, which has raised funds in part by selling pro-Trump apparel and merchandise.

“It’s OK to deny 2020,” reads two shirts still being sold on the outlet’s website. Another shirt promotes the refuted claim that Jan. 6, 2021, was an “FBI setup to frame Trump supporters as insurrectionists,” as the shirt says.

And Beattie has become a frequent guest on other right-wing media, often promoting conspiracy theories related to Jan. 6.

On Donald Trump Jr.’s podcast last month, Beattie repeated his claims that the FBI knows who’s behind the pipe bombs left at DNC and RNC offices on Jan. 6 but “what they found out was profoundly embarrassing to the government and to the narrative that the Biden regime wanted to promote, and so instead of following that investigation further, they basically just killed it,” Beattie said.

Beattie also claimed that surveillance video released by the FBI to seek help in identifying the perpetrator was “clearly tampered with.”

In mid-August 2018, he made national headlines, with the Washington Post reporting then that he “was terminated last week after revelations that he had spoken at a conference attended by well-known white nationalists” two years earlier.

According to the Washington Post, Beattie – who is Jewish – insisted that he was not racist and said in a statement.

“In 2016 I attended the [H.L. Mencken Club] conference in question and delivered a stand-alone, academic talk titled ‘The Intelligentsia and the Right.’ I said nothing objectionable and stand by my remarks completely,” the statement said. “It was the honor of my life to serve in the Trump Administration. I love President Trump, who is a fearless American hero, and continue to support him one hundred percent.”

At the end of the Trump administration, in November 2020, the Trump White House appointed Beattie to a three-year term with the Commission for the Preservation of America’s Heritage Abroad, which helps preserve sites related to the Holocaust.

The Anti-Defamation League strongly objected to the appointment, issuing a statement at the time saying, “It is absolutely outrageous that someone who has consorted with racists would even be considered for a position on a commission devoted to preserving Holocaust memorials in Europe.”

The New York Times then asked Beattie for comment, and he told the paper: “The ADL pretends to be an organization that protects Jews, but it really exists to protect Democrats. As a Jewish Trump supporter, I consider it an honor to be attacked by the far-left ADL and its disgraced leader, Jonathan Greenblatt.”

Asked about Beattie’s new position at the State Department, a White House spokesperson referred ABC News to the State Department. First reached on Friday, the State Department has so far not commented.

On Sunday, Beattie did not immediately respond to a request for comment by ABC News.