The Federal Reserve should be prepared to adjust its policy to protect the U.S. economy from any sustained pressure from a global economic slowdown and volatility in financial markets, the Fed's second-in-command said on Thursday.

The speech by Fed Vice Chairman Richard Clarida reinforced a message of patience and possible re-calibration given by several of his colleagues in recent days, including Chairman Jerome Powell who earlier in the day said the U.S. central bank would be watching to see whether such risks become reality.

Clarida said overseas growth had "moderated somewhat" in recent months, while a sell-off in stocks and run-up in market yields meant financial conditions have "materially" tightened.

"These recent developments ... represent crosswinds to the U.S. economy. If these crosswinds are sustained, appropriate forward-looking monetary policy should seek to offset them," he said at a Money Marketeers dinner in New York.

"We can afford to be patient about assessing how to adjust our policy stance, he said. This is in part because "we begin the year as close to our assigned objectives as we have in a very long time," he added of the goals of maximum sustainable employment and low and stable inflation.

The Fed hiked rates four times last year including in December, when policymakers' forecasts predicted a median of two more hikes in 2019. Yet markets sold off aggressively through the last three months of the year, reflecting concerns over global growth and a U.S.-China trade war.

Clarida said economic conditions are favorable going into this year and he predicted the economy would continue expanding above potential, as it did last year.

But he noted that recently weaker inflation readings raised questions about how permanently it would remain near a 2-percent target. He repeated the Fed's newfound mantra that monetary policy, including the ongoing shedding of assets, is not on a "pre-set course."