Sen. Markwayne Mullin, R-Okla., said Sunday that he doesn’t “believe for one second” that Russia would invade any other country right now out from “fear” of President Donald Trump.

Mullin made the remarks in an interview on NBC News’ “Meet the Press” on Sunday, reacting to Ukrainian President Volodymyr Zelenskyy’s recent warning that Russia is amassing troops in Belarus with an eye toward attacking a NATO country.

“First of all, I don’t believe for a second that Russia’s going to advance a war in any other country right now. It would be extremely dangerous, and he will call President Trump’s hand,” Mullin said. “President Trump does not just simply say idle words, he delivers it.”

Mullin recalled what happened in 2017 when Trump “told Russia to stay out of” the civil war in Syria.

Russia “went ahead and helped [Bashar] Assad and they delivered chemical weapons on their own people. What did President Trump do? Within 30 minutes, they kicked Russia out of the airspace and completely destroyed their airfield they were operating underneath. Russia and Putin fears President Trump,” Mullin said.

Further, Mullin said the U.S. should “absolutely” remain in NATO so long as “it’s in our best interest.”

“But right now, NATO has not always been playing in our best interest … and we should re-look at things. The definition of insanity is doing the same thing and expecting different results. We see NATO, we see U.N. sometimes weaponizing against the United States and we’re the biggest funder of it,” he said.