In this March 9, 2016 file photo, Attorney General Loretta Lynch testifies on Capitol Hill in Washington, before the Senate Judiciary Committee. Associated Press/Andrew Harnik Former FBI Director James Comey told the Senate Intelligence Committee that former Attorney General Loretta Lynch had made him uncomfortable when she asked him to refer to the probe into Hillary Clinton's emails a "matter" instead of an "investigation."

"That gave me a queasy feeling," Comey said, adding that Lynch's directive "confused me and concerned" him.

"That was one of the bricks in the load that led me to conclude I have to step away from the department if we're to close this case credibly," Comey continued.

Comey brought up Lynch's request after being asked by the committee chairman, Sen. Richard Burr, whether his decision last July to publicly announce the results of the FBI's investigation into Clinton's emails was due to a widely criticized meeting on an airport tarmac the previous month between Lynch and former President Bill Clinton.

Although both Lynch and Bill Clinton have denied they discussed the email probe during their private meeting and instead made small talk about golf and Clinton's grandchildren, both received intense blowback over creating the appearance of impropriety during an ongoing investigation. At the time of the tarmac meeting, Hillary Clinton was the Democratic nominee for president.

That backlash ultimately led Lynch to say she would accept the findings of the FBI and career prosecutors who were investigating Clinton's use of a private email server when she was secretary of state.

In his testimony, Comey confirmed that the tarmac meeting was the deciding factor in making his announcement independently from the Department of Justice.

"In an ultimately conclusive way, that was the thing that capped it for me," Comey testified. "I had to do something separately to protect the credibility of the investigation, which meant both the FBI and the Justice Department."

Comey then said that several other events contributed to his decision to make the announcement — one of which was the tarmac meeting, the others Comey said he could not discuss in an open session.