The State Department’s acting inspector general is resigning from his role after less than three months in the position to return to the private sector, the agency announced Wednesday.

Acting Inspector General Stephen Akard will be replaced by Diana Shaw, who will take on the watchdog role in an acting capacity as well. Shaw previously served as deputy inspector general.

Akard will also be leaving his position as director of the Office of Foreign Missions.

"Ambassador Stephen J. Akard, the State Department’s Acting Inspector General and the Director of the Office of Foreign Missions, has announced he is returning to the private sector after years of public service,” a State Department spokesperson said.

“We appreciate his dedication to the Department and to our country. The Deputy Inspector General, Diana R. Shaw, will become the new Acting Inspector General.”

Ackard’s appointment as acting inspector general in May, following the abrupt firing of the agency watchdog Steve Linick by President Trump and at the request of Secretary of State Mike Pompeo, drew concern from Democrats and critics who questioned how a watchdog could be in a position to investigate himself.

Shaw joined the State Department's Office of Inspector General in May, coming from the watchdog office at the Department of Homeland Security where she spent almost four years, according to her LinkedIn profile. It is unclear if she began before or after Linick was fired on May 15.

Ackard wrote to Democrats in June that he had recused himself from numerous areas in the department, including the operations of Office of Foreign Missions, issues he had worked on previous to taking over as watchdog and that he would recuse himself “from matters involving individuals with whom I have a personal relationship such that my objectivity could be impaired.”  

Democrats are investigating the ouster of Linick, raising concerns that the watchdog was dismissed as political retaliation for conducting at least two inquiries into Pompeo, including the misuse of agency funds for personal use of he and his wife and the secretary’s role in pushing through an $8 billion arms sales to Saudi Arabia and other Middle East countries without congressional oversight.

Democrats this week issued four subpoenas for top aides to Pompeo as part of their investigation, including Under Secretary of State for Management Brian Bulatao, a close ally of the secretary's and a superior to Akard in his position as director of the Office of Foreign Missions.

An inspector general report on the arms sale is believed to be completed and undergoing review by the State Department for response, as is typical, before its public release.

Pompeo said he recommended Linick’s firing because he was undermining the mission of the State Department. Linick testified to House lawmakers that he has never heard any justification for his firing. 

Pompeo canceled a scheduled press conference Wednesday morning following the news of Ackard’s resignation.