Federal Reserve Bank of Philadelphia President Patrick Harker said in a speech on Tuesday that the Fed should not raise its interest rate further until inflation picks up.

"It might prove prudent to wait until the inflation data are stronger before we undertake a second rate hike," he said.

Harker added that inflation could be negative in the first quarter.

Federal Reserve Bank of Philadelphia president noted that the Fed could hike its interest rate further in the second half of 2016.

Harker is not a voting member of the Federal Open Market Committee (FOMC) this year.