Philadelphia Fed President Patrick Harker said on Friday that the Fed should start its interest rate sooner rather than later.

"I would like to see rates raised sooner rather than later. With an early start, we can better ensure that monetary accommodation is removed gradually and that inflation returns to the Fed's 2 percent target smoothly. My fear is that the Federal Reserve risks losing its credibility and only adds uncertainty to the economic landscape the longer the Committee waits to begin normalizing policy," he said.

"Raising rates this year will, in my view, serve to reduce monetary policy uncertainty and to keep the economy on track for sustained growth with price stability," Harker added.

Philadelphia Fed president expects steady and modest growth in the U.S.