Mueller has asked for documents on Trump’s reasons for firing former national security advisor Michael Flynn and ex-director of the FBI James Comey, the New York Times reported on Wednesday.
Unnamed White House officials told the Times says Mueller has requested official documents on 13 different areas. One of which is a meeting with Russian officials in which Trump said firing Comey relieved “great pressure” on him.
Comey was fired in May, while he was leading the Russia investigation. The White House initially said the dismissal was on the recommendation of Deputy Attorney General Rod Rosenstein, but Trump later said he would have fired Comey anyway.
Trump met with Russian Foreign Minister Sergei Lavrov on May 10 in the Oval Office — one day after the dismissal.
“I just fired the head of the FBI. He was crazy, a real nut job,” Trump said, according to a document obtained by the Times at the time.
“I faced great pressure because of Russia. That’s taken off.”
On Tuesday, Mueller’s probe questioned Deputy Attorney General Rod Rosenstein on the firing of Comey.
WATCH: Ongoing coverage of the Russia probe on Globalnews.ca
Another area which Mueller is investigating is Trump’s decision on how to respond to reports of a meeting between his son, Donald Jr., and Russian nationals during the election campaign.
In June 2016, Trump Jr. agreed to meet a woman whom he thought was a Russian government lawyer who might have dirt on Democratic nominee Hillary Clinton.
When the meeting came to light in July, 2017, the Washington Post reported that when Trump advisors suggested disclosing the details of the meeting Trump decided to change the plan and “personally dictated a statement in which Trump Jr. said he and the Russian lawyer had ‘primarily discussed a program about the adoption of Russian children.’”
Mueller is also looking into other actions taken while Trump has been in office, which include Flynn’s resignation.
Flynn was one of the first of Trump’s team to be let since he took office in January. He officially resigned – reportedly at the request of the president – in February after his contacts with Russia came to light.