Tucker Carlson previewed his upcoming interview with President Donald Trump, scheduled to air Tuesday, July 17 at 8:00 p.m. ET on "Tucker Carlson Tonight."

Carlson joined "The Five" to take questions on his discussion with the president, which taped moments after the joint press conference with Russian President Vladimir Putin.

Carlson said he read some of the responses from critics of the summit, but added that Trump was "not particularly moved by them."

"He thinks that Russia is not the primary threat to the U.S. -- China is," Carlson said, adding that Trump found it "absurd to pass up the chance" to be closer to Russia for the sake of international relations.

Carlson said NATO was the subject of some discussion during his interview with the president.

Carlson said he himself does not completely understand why NATO is still in existence as we know it.

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Carlson said one of NATO's initial objectives was to keep the Soviets from encroaching on Western Europe -- but now, if a nation such as Montenegro is threatened by another country, Carlson's children could be tasked to defend the tiny NATO nation to no direct U.S. benefit.

He said Trump found those questions thought-provoking as well.

Trump also appeared less concerned with his critics and less inclined to pay "lip service" to neoconservatives in Washington either, Carlson said.

Check out preview clips below and watch the full interview on "Tucker Carlson Tonight" Tuesday at 8:00pm ET on Fox News Channel.

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