NORTH CAROLINA -- After the President’s headline-grabbing trip abroad, North Carolina’s Sen. Thom Tillis is walking a fine line, comforting allies while avoiding outright criticizing the president from his own party.

As the President hopscotched across Europe, America’s long-standing allies were left on edge. On Thursday, Tillis offered reassurance.

“I do not believe the President has any intention of withdrawing from NATO. I do believe that the President uses various devices to capture people's attention,” he said during an event at the Center for Strategic and International Studies (CSIS).

The Republican co-chairs the Senate NATO Observer Group, a bipartisan assembly of lawmakers that serves as a liaison to the treaty alliance and its members. He attended the summit last week, participating in a forum.

“The NATO alliance is critically important and we have to make sure that we do our role of communicating the importance of it,” he said Thursday.

While at the summit, President Donald trump signed on to a document reaffirming America’s commitment to the treaty alliance. However, days later, he threw the key promise of collective defense into question again in an exchange on Fox News.

"Why should my son go to Montenegro to defend it from attack?" asked host Tucker Carlson.

"I understand what you're saying. I've asked the same question. You know Montenegro is a tiny country with very strong people,” the president replied.

On this, Tillis did not mince words, saying the U.S. will back up and defend its allies.

“We have an obligation under the treaty to do exactly what nations did after 9/11. Period, end of story,” he said, referring to NATO’s support in the aftermath of the terrorist attack.

The most dramatic moment of the president’s trip was in Helsinki, when the president appeared to cozy up to Russian leader Vladimir Putin while questioning U.S. intelligence on the topic of Russian election meddling.

While President Trump has since walked back some of his statements, Tillis offered a warning about Putin.

“The way you can tell he is being dishonest on Russian meddling, whether it’s in our elections or any of these other nations, is his lips are moving,” he said.

The White House Spokeswoman announced Thursday via Twitter that the president is asking his senior advisor to invite Putin to Washington, D.C. in the fall for another meeting.

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