Secretary of State Mike Pompeo declined to be interviewed by the Office of the Inspector General about his push for “emergency” arms sales to Saudi Arabia and the United Arab Emirates, according to a congressional aide and a source with knowledge of the investigation. Pompeo instead submitted answers in writing to the OIG, according to the source.

The interaction with the staff for Inspector General Steve Linick came before Linick was fired last Friday night by President Donald Trump at Pompeo’s request — calling into question whether it was retaliation for or obstruction of the OIG’s work.

The administration has not provided a reason for why Linick was fired. But Pompeo has denied it was retaliation, telling the Washington Post in an interview Monday that he was unaware of OIG investigations and therefore it was “simply not possible for this to be an act of retaliation.”

During a press conference Wednesday, however, he confirmed that he was aware of one “particular investigation” and submitted answers in writing for it “some time earlier this year,” without specifying which probe. The OIG is also investigating whether Pompeo used a political appointee to run personal errands like walking the dog and picking up dry cleaning.

The top U.S. diplomat conflated those two in dismissing the reports as “crazy stuff,” telling reporters he had heard, “Someone was walking my dog to sell arms to my dry cleaner. I mean, it’s all just crazy.”

No one has suggested the issues were related. When asked, Pompeo again declined to provide a reason for Linick’s removal beyond saying, “I frankly should have done it some time ago. … Unlike others, I don’t talk about personnel matters. I don’t leak to y’all,” he added, saying the department will share its rationale “with the appropriate people.”

While admitting he was aware of at least one investigation, Pompeo shifted the goalposts and said it still wasn’t possible for the firing to have been retaliation because he didn’t know the scope or nature of the probe or whether it has been completed or is continuing: “I don’t have any sense of that. Again, it’s not possible for there to have been retaliation.”

An OIG spokesperson said they cannot confirm or deny the existence of any investigations.

While Trump’s letter to congressional leaders said only that he “no longer” had confidence in him, he told reporters days later at the White House that he did it at Pompeo’s request.

“I said look, I will terminate him. I don’t know what’s going on other than that, but you would have to ask Mike Pompeo, but they did ask me to do it, and I did it,” Trump said Monday.

The inspector general is an independent federal watchdog with oversight of the agency. All inspectors general serve at the president’s appointment and can be fired by the White House, although they are confirmed to their role by the Senate.

In a statement to ABC News, the chairman of the House Foreign Affairs Committee, Rep. Eliot Engel, D-N.Y., said that the OIG’s investigation into the Saudi weapons sale “may be another reason for Mr. Linick’s firing.”

In May 2019, Pompeo’s State Department declared an emergency so that the administration could bypass congressional approval to send $8 billion of weapons to Saudi Arabia and the United Arab Emirates amid their ongoing war in neighboring Yemen.

Congress has the authority to approve or reject U.S. arms sales and transfers. Republican and Democrat lawmakers opposed the sales, particularly because Saudi agents murdered and dismembered Washington Post columnist Jamal Khashoggi and the Saudi-led coalition had been using American-provided bombs to target civilians and civilian infrastructure in Yemen, according to the United Nations and monitoring groups on the ground.

There was “intense pressure” on staff from the White House and Pompeo to get congressional approval for the sales, according to a former senior administration official, but after weeks of talks between administration officials and senior lawmakers and their staffs, lawmakers refused to lift the informal “hold” they had on the deals.

In the face of that opposition and a possible vote to block the sales, the White House asked its agencies to “break the holds” by using an emergency declaration, according to the former official. Officials from the State Department and Pentagon were opposed “because there was not an emergency, especially since it would take years for most of the weapons to be delivered,” and because the intelligence community assessment would not support an emergency, the former official told ABC News.

After those legal issues were raised, the policy process led by the National Security Council ended, and the decision to move forward was made by Pompeo and then-acting Defense Secretary Patrick Shanahan, the former official added. The legal justification cited an urgent threat from Iran and the Houthi rebels in Yemen that Tehran supports.

The move sparked even greater outrage, even among Republican allies on the Hill. But ultimately, the resolutions of disapproval that Congress passed and would have blocked the sales were vetoed by the president, and Congress failed to secure enough votes to override his veto.

House Speaker Nancy Pelosi said Pompeo “undermined the will of Congress” in declaring a “a fake emergency” to sell the arms to the Saudis and Emiratis. She called on Pompeo to testify before Congress, but said it was unlikely because the White House would block it.

Engel said in his statement that the State Department OIG “was investigating — at my request — Trump’s phony declaration of an emergency so he could send weapons to Saudi Arabia. We don’t have the full picture yet, but it’s troubling that Secretary Pompeo wanted Mr. Linick pushed out before this work could be completed,” according to Engel.

Engel and his Senate colleague Bob Menendez, D-NJ, the top Democrat on the Senate Foreign Relations Committee, announced Saturday they were investigating Linick’s firing, demanding the White House, State Department, and OIG turn over any documents related to his removal by this Friday.

Asked if he would comply, Pompeo instead turned to attack Menendez directly, accusing his office of leaking details about the OIG.

“I don’t get my ethics guidance from a man who has criminally prosecuted — case number 15-155 in New Jersey federal district court,” Pompeo said — a reference to federal corruption charges filed against Menendez in 2015 for accepting gifts and illegal campaign contributions from a Florida doctor. The federal judge overseeing his case ultimately declared a mistrial, and a second federal judge dismissed the remaining charges. The Justice Department in 2018 dropped its case after initially announcing it would retry him on some of the charges.