As was widely expected, Fed policymakers on Wednesday left the central bank's overnight rate unchanged at a range of 4.25% to 4.5%.

Her resignation now paves the way for Trump to put his own nominee in for the board. Two of his prior appointments, Christopher Waller and Michelle Bowman, voted against the decision at Wednesday's meeting to hold the Fed's key rate steady, instead indicating they wanted to lower. Kugler was absent for the vote.

Fed Chair Jerome Powell said the economy is solid — and that it's also too early to tell how tariffs will affect it.