Republican Utah Sen. Mitt Romney announced Friday that he will vote to hear from additional witnesses in the Senate impeachment trial of President Donald Trump.

Romney had previously indicated that he wanted to hear from witnesses, including former National Security Adviser John Bolton, and Bolton’s communications director Liz Johnson officially confirmed the senator’s intentions in a tweet Friday. (RELATED: Romney Remains #NeverTrump, Has No Plans To Endorse POTUS In 2020)

“He wants to hear from Ambassador Bolton, and he will vote in favor of the motion today to consider witnesses,” Johnson said.

For those asking: As @SenatorRomney has said, he wants to hear from Ambassador Bolton, and he will vote in favor of the motion today to consider witnesses. — Liz Johnson (@LJ0hnson) January 31, 2020

Romney is the second Republican senator to come out in favor of calling witnesses, alongside Maine Republican Senator Susan Collins. The Senate is expected to vote Friday on whether or not to hear additional witnesses. ABC News reported Thursday that Republican Senate Majority Leader Mitch McConnell believes he has the votes to defeat witnesses. (RELATED: Zelensky Says He’s Never Met Rudy Giuliani)

The freshman senator has been a frequent Trump critic since the president’s 2016 campaign and has criticized Trump’s July phone call with Ukrainian President Volodymyr Zelensky, which led to Trump’s impeachment. (RELATED: Rick Scott Rips Mitt Romney, Compares Him To Nancy Pelosi)

“I did read the transcript. It remains troubling in the extreme. It’s deeply troubling,” Romney said at the time. “Clearly what we’ve seen from the transcript itself is deeply troubling.”

If the senate does not vote to hear from additional witnesses, the president is expected to be acquitted as early as Friday night.