Federal Reserve Bank of Boston President Eric Rosengren said Wednesday he is willing to hold off on more rate increases until there is greater clarity over the economic outlook.

“With two very different scenarios—economic slowdown implied by financial markets; or growth somewhat above potential GDP growth, consistent with economic forecasts—I believe we can wait for greater clarity before adjusting policy,” Mr. Rosengren said in the text of a speech prepared for delivery before an event in Boston. “Current monetary policy...