President Trump continued his purge of inspectors general late Friday, moving to oust Steve A. Linick, who had served in that post at the State Department since 2013, and replacing him with an ambassador with close ties to Vice President Mike Pence. The decision to remove Mr. Linick, first reported Friday night by Politico, is the latest in a purge of inspectors general whom Mr. Trump has deemed insufficiently loyal to his administration, upending the traditional independence of the internal watchdog agencies whose missions are to conduct oversight of the nation’s sprawling bureaucracy.

The House Intelligence Committee concluded that President Trump tried to “use the powers of his office to solicit foreign interference on his behalf in the 2020 election.”

President Trump threatened on Friday to quickly revoke the security clearance of Bruce Ohr, a little-known Justice Department official, for the first time seeking to apply his power to cut access to sensitive information to a midlevel government worker rather than a prominent former national security official.

President Trump acknowledged publicly for the first time on Friday that he was under investigation in the expanding inquiry into Russian influence in the election, and he appeared to attack the integrity of the Justice Department official in charge of leading it.

A longtime friend of President Trump said on Monday that Mr. Trump was considering whether to fire Robert S. Mueller III, the special counsel investigating possible ties between the president’s campaign and Russian officials. The startling assertion comes as some of Mr. Trump’s conservative allies, who initially praised Mr. Mueller’s selection as special counsel, have begun trying to attack his credibility.

President Trump announced Thursday that he will withdraw the United States from participation in the Paris climate accord, weakening global efforts to combat climate change and siding with conservatives who argued that the landmark 2015 agreement was harming the economy.