Washington (CNN) Special counsel Robert Mueller has requested documents and information covering a range of events from President Donald Trump's White House, including two firings and an Oval Office meeting, sources familiar with the matter tell CNN.

Mueller's investigators are looking for documents and emails relating to the dismissals of national security adviser Michael Flynn and FBI director James Comey, according to the sources. In addition, one source confirms that Mueller's team wants information connected to the Oval Office meeting Trump had with Russian officials in which he bragged about firing Comey, saying it eased pressure on his White House.

The requests show that parts of Mueller's investigation are focusing on the President's own actions.

"I just fired the head of the FBI. He was crazy, a real nut job," Trump reportedly said during the May conversation in the Oval Office, according to the Times . "I faced great pressure because of Russia. That's taken off."

White House attorney Ty Cobb told CNN that "out of respect for special counsel and his process," the White House does not comment on its communications with the special counsel.

The White House is committed to fully cooperating with the special counsel, he added.

When asked Thursday whether he believed Mueller was exceeding his jurisdiction, Vice President Mike Pence responded, "that's for others to say."

"What I can assure you is that we're fully cooperating with the special counsel, and we'll continue to do that," he said on "CBS This Morning." "I've made clear that during my time on the campaign, I was not aware of any contacts or any collusion with Russian officials."

Additionally, two sources familiar with the matter said Mueller has expressed interest in speaking with former and current White House staffers whom investigators consider witnesses, including former chief of staff Reince Priebus, former press secretary Sean Spicer, communications director Hope Hicks, White House counsel Don McGahn, communications adviser Josh Raffel and associate counsel James Burnham. No interviews have been set up yet, according to a source familiar with the matter.

Mueller's team also approached the White House about interviewing staffers who were aboard Air Force One for the creation of the initial response to news of Donald Trump Jr.'s Trump Tower meeting with a Russian lawyer, sources previously told CNN

Mueller also asked the White House to save all the documents relating to Trump Jr.'s Trump Tower meeting, according to a source who had seen the notice, CNN reported in July

The Times also reported Tuesday that Mueller's office recently sent a document to the White House outlining 13 areas that investigators want additional details on.

Mueller's team has not reached out for any additional documents or information from Trump.