Republican Sen. Markwayne Mullin reaffirmed on Sunday that President Donald Trump has the capability to apply pressure to Russian President Vladimir Putin to negotiate a deal to end the war in Ukraine.

       "Putin knows the one person that can truly change the war is the United States," the Oklahoma sentor told co-anchor Jonathan Karl on ABC News' "This Week." "If we went all-in for Ukraine, if we went all-in with the resources we have, from air superiority to the weapons that we can deploy to Ukraine, Putin knows at that point he would be in a extremely negative position."

       "I think that being the opportunity for President Trump to talk to Putin and say, 'Listen, we want to end the war. We don't want to have to engage more, but we're not going to allow you to move forward. So let's negotiate a peace deal here, or you're going to force our hand to be farther involved,'" Mullin said.

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