The head of the U.S. central bank said "the time has come" to adjust the monetary policy, implying a possible rate cut in September, without elaborating on the pace of the downward rate adjustment.

At the Kansas City Fed's annual research conference in Jackson Hole, Wyoming on Friday, Federal Reserve Chairman Jerome Powell said while the "direction of travel is clear," the timing and pace of cuts would depend on data, leaving the door open to a "big cut" of point-five percentage point.

Powell said his "confidence has grown that inflation is on a sustainable path back to two percent," after rising to about seven percent during the COVID-19 pandemic, and that the upside risks have diminished.

He, however, said a slowdown in the labor market is "unmistakable" and "the downside risks to employment have increased," pledging to do everything possible to support a strong labor market on a progress toward price stability.

The Fed has kept its key lending rate at roughly five-point-three percent, a two-decade high, since last July.