Washington (CNN) White House chief of staff John Kelly told reporters on Friday that the White House's handling of classified material "wasn't up to the standards" he had previously seen in his governmental career.

During an impromptu meeting with reporters after President Donald Trump had departed for the weekend, Kelly explained the security clearance process for White House officials.

"It came to my notice that the kind of things I was used to in (Department of Defense) in terms of the handling of classified material wasn't up to the standards that I'd been used to," he said.

Though Kelly said it was "nothing illegal," he added that it "wasn't quite up to the standards" he had been used to while working as a military general at the Pentagon. Kelly noted that the standards at the White House had to be raised, and that's when he noticed that a number of people did not have final security clearance. He chalked that up to the fact that most of the White House staffers have never worked in government before.

Kelly went into more detail Friday about lapses in the security clearance process than any White House official to date. White House press secretary Sarah Sanders has repeatedly told reporters she does not discuss the individual security clearances of White House officials.

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