The Federal Reserve may soon be drawn into the Trump administration’s efforts to back the embattled currency of U.S. ally Japan.

Treasury Secretary Scott Bessent wants the apolitical Fed to expand a lending facility that would enable Japan to support its currency without roiling the sensitive U.S. Treasurys market. That request comes as new Fed Chairman Kevin Warsh is seeking to rewrite the relationship between the Treasury and the Fed. How the two collaborate could have important consequences for the management of the $29 trillion Treasurys market and could see the Fed take on a new role backing U.S. financial diplomacy.

It isn’t clear how much support the chairman has within the Fed for major policy changes. The Fed declined to comment.

The Treasury didn’t respond to a request for comment about its plans.