President Trump has long hectored the Federal Reserve to lower borrowing costs. One of its top officials thinks the central bank should do so at its next meeting, which takes place at the end of month.

Christopher J. Waller, a Fed governor who was appointed by Mr. Trump in his first term and is seen as a potential contender to be the next Fed chair, laid out the case on Thursday for a quarter-point rate cut when the central bank next votes on monetary policy on July 30. He also endorsed further interest rate cuts this year.

His argument rests on an assumption that price pressures stemming from Mr. Trump’s sweeping tariffs will not lead to a persistent inflation problem but only a temporary burst. He also said there had been a substantial softening in the labor market, and that the economy was poised to grow at a much slower pace this year.

Mr. Waller advocated for returning the Fed’s policy settings to “neutral,” meaning interest rates at a level that neither speeds up nor slows down business activity.

“With inflation near target and the upside risks to inflation limited, we should not wait until the labor market deteriorates before we cut the policy rate,” he said at an event hosted by New York University on Thursday.

Mr. Waller’s comments come at a tumultuous moment for the Fed. Mr. Trump has intensified his pressure campaign on Jerome H. Powell, the central bank chair, and has openly toyed with firing him before his term ends next year. During a meeting with roughly a dozen House Republicans on Tuesday, the president showed off a draft letter firing Mr. Powell and asked whether he should send it. He later said that it was “highly unlikely” that he would follow through with ousting Mr. Powell unless he had committed “fraud.”