Sen. Thom Tillis, R-N.C., is digging in on his threat to block all Federal Reserve confirmation votes until the Justice Department concludes its investigation into outgoing Chairman Jerome Powell.

While praising President Donald Trump’s decision to nominate Kevin Warsh to succeed Powell in May, Tillis said Friday he cannot support any Federal Reserve nominee as long as the DOJ probe remains unresolved.

“Kevin Warsh is a qualified nominee with a deep understanding of monetary policy,” Tillis wrote in a post on X. “However, the Department of Justice continues to pursue a criminal investigation into Chairman Jerome Powell based on committee testimony that no reasonable person could construe as possessing criminal intent.”

Tillis, who is not seeking reelection this November, framed his opposition as a matter of principle, warning that the investigation threatens the independence of the central bank.

“Protecting the independence of the Federal Reserve from political interference or legal intimidation is non-negotiable,” he added.

The North Carolina senator first raised objections earlier this month, signaling he would oppose any Fed nominee while the DOJ investigation into Powell remains active.

The Justice Department subpoenaed the Federal Reserve on Jan. 9 as part of an inquiry tied to Powell’s June Senate testimony regarding sharply rising renovation costs at the Fed’s headquarters.

Trump has said he had no knowledge of the Justice Department’s investigation.

“My position has not changed: I will oppose the confirmation of any Federal Reserve nominee, including for the position of Chairman, until the DOJ’s inquiry into Chairman Powell is fully and transparently resolved,” Tillis concluded in his Friday post.

Tillis has frequently broken with Trump.

Most recently, he opposed the president’s One Big Beautiful Bill Act, prompting Trump to publicly criticize him. Tillis has also challenged Trump’s efforts to contest the 2020 election and previously blocked a Trump-backed U.S. attorney nominee.

Trump later mocked Tillis on Truth Social and praised his decision not to seek reelection, underscoring the long-running tension between the two Republicans.

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