San Francisco Fed President John Williams said on Tuesday that two or three interest rate hikes this year would be appropriate. He pointed out that it did not matter when to raise the interest rate.

"We stay on this kind of basic path of raising interest rates gradually over the next couple of years, that's kind of what's important for financial conditions," Williams added.

He noted that the Fed's interest rate hikes would not lead to a lot of turmoil in financial markets.

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