May 19, 2020
President Donald Trump fired Steve Linick, the agency's inspector general, on Friday night.
He had been investigating Mr Pompeo's alleged use of government staff for personal errands, US media reported.
It emerged on Monday he was also scrutinising a Trump administration Saudi arms deal.
He is the fourth inspector general (IG) to be fired by Mr Trump in four weeks, and the move sparked outcry from Democrats, who claimed Mr Linick was fired for political reasons.
Mr Pompeo confirmed that he had recommended Mr Linick's removal, but said he did not know that the inspector general was investigating him.
"I'm not briefed on it. I usually see these investigations in final draft form 24 hours, 48 hours before the IG is prepared to release them," he told the Washington Post on Monday.
"So it's simply not possible for this to be an act of retaliation. End of story."
The secretary of state said Mr Linick was sacked for "undermining" the state department, though he did not give further details.
"I went to the president and made clear to him that Inspector General Linick wasn't performing a function in a way that we had tried to get him to, that was additive for the state department, very consistent with what the statute says he's supposed to be doing," he said.