Just before the administration officially hits the 100-day mark, Martha MacCallum sat down with President Donald Trump for an exclusive interview that will air tonight at 7:00pm ET on Fox News Channel.

"The First 100 Days" anchor talked with President Trump at the White House in a wide-ranging exclusive interview covering the big issues from his first three months in office.

Behind the scenes of my conversation with President Trump #first100 pic.twitter.com/CMfEBggMvX — martha maccallum (@marthamaccallum) April 28, 2017

No topic was off-limits, as Martha pressed the president on topics like Michael Flynn, North Korea, health care, the border wall and more.

MacCallum asked Trump about the exit of his former national security adviser Michael Flynn and the investigation into foreign payments Flynn received from Turkey and Russia.

The White House has pushed back on Democrats' accusations that they're not cooperating with the probe.

Trump said the Obama administration had already vetted and approved Flynn for a security clearance and that there were "years left on that approval."

Flynn was head of the Defense Intelligence Agency, but was fired in the spring of 2014.

Watch the clip above.

MacCallum asked Trump about critics who say he has not passed any "major legislation" in his first 100 days in office.

Trump said that's "really wrong" and that 28 bills have been passed since he took office.

MacCallum questioned Trump on whether he is "disappointed" by Republicans' failure to pass a health care bill.

"Yeah. I’m disappointed. ... I'm disappointed that it doesn't go quicker," he answered, adding that House Speaker Paul Ryan is "trying very hard" to get things done in a "very tough system."

Watch the full interview tonight at 7:00pm ET on Fox News Channel and don't miss Monday's debut of "The Story with Martha MacCallum" at the same time.

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