President Trump said that he may declare a national emergency over the southern border amid an impasse with Democrats over the need for a wall.

"I have the absolute right to declare a national emergency," Trump said after stating, correctly, that other presidents have used it, some fairly often. "I haven't done it yet. I may do it. If this doesn't work out, probably I will do it. I would almost say definitely," the President said.

When asked why he hadn't already declared it, Trump said, “Because I would like to do the deal through Congress, and because it makes sense to do it through Congress."

He said "the easy route" would be to simply call the national emergency.

Why this is significant: By declaring a national emergency, Trump allies hope he can then find the funds needed to build the wall without Congressional authorization. Senior Republicans, however, have cautioned against it.

Senate Majority Whip John Thune earlier on Thursday raised concerns about that possibility, saying it could get tied up in the courts and would set a concerning precedent.

“Frankly I’m not crazy about going down that path,” Thune told CNN. “Inevitably, I suspect it probably gets challenged in court.”