Army Col. Douglas MacGregor (Ret.) said Friday that it'd be "absolutely" wise for President Trump to declare a national emergency in order to secure the U.S. border.

Trump said Friday that there is a "good chance" he'll make such a declaration if funding for a wall along the border cannot be agreed to.

Government funding is set to expire on Feb. 15, and lawmakers have until then to reach a border security agreement or be faced with another potential shutdown.

MacGregor said on Tucker Carlson Tonight that only Trump himself can address a potential declaration of emergency.

"He has the constitutional authority to do so," he said. "What he needs is an executive order."

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MacGregor said Trump does not need "special permission" to act on what he feels is necessary in order to secure the border.

"This is a national emergency. Let there be no doubt about it," he said.

He said that Trump has the power to outline legal restrictions in an executive order on expelling illegal immigrants, and he should do so "as soon as possible."

MacGregor added, though, that Trump has surrounded himself with people who want to subvert him.

"Everyone is there to tell him no, and that's not an answer he should accept," he said. "He has the authority. He needs to act."

Watch the discussion above.

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