Federal Reserve Chair Jerome Powell made it clear on Wednesday that the resilient U.S. labor market is currently the primary determinant of monetary policy, a signal that strong July employment figures could snuff out all bets for a September rate cut and reduce the likelihood of any further easing this year.

Jerome H. Powell, the Federal Reserve chair, is facing relentless attacks from the president, a lively campaign to replace him and divisions in his own ranks over when to cut interest rates.