WASHINGTON — President Trump moved on Tuesday to oust the leader of a new watchdog panel charged with overseeing how his administration spends trillions of taxpayer dollars in coronavirus pandemic relief, the latest step in an abruptly unfolding White House power play against semi-independent inspectors general across the government.

The official, Glenn A. Fine, has been the acting inspector general for the Defense Department since before Mr. Trump took office and was set to become the chairman of a new Pandemic Response Accountability Committee to police how the government carries out the $2.2 trillion coronavirus relief bill. But Mr. Trump replaced Mr. Fine in his Pentagon job, disqualifying him from serving on the new oversight panel.

The move came at a time when the president has been reasserting authority over the executive branch and signaling impatience with independent voices within the government that he considers disloyal. In recent days, he fired an inspector general who reviewed the whistle-blower complaint that led to his impeachment, nominated a White House aide to another key inspector general post, declared that he would ignore certain oversight provisions in the new relief law and attacked another inspector general who criticized virus testing shortages.

Mr. Trump even cheered the firing of the captain of an aircraft carrier for sending a letter to fellow Navy officers pleading for help for his virus-stricken crew, castigating the officer for airing unfavorable information. Only after a loud backlash over the firing and the acting Navy secretary’s speech calling the captain “stupid” did the president partly reverse himself and say he would look into it. The acting Navy secretary, who said he had ordered the firing because he assumed Mr. Trump might have done it himself otherwise, took the hint and resigned on Tuesday.