Lawmakers and others across the political spectrum are expressing worry over Donald Trump’s threat to close the southern border within days over movement of so-called “caravans” of Central American refugees looking to come to the United States.

Among the issues at stake is the future of Trump’s proposed trade agreement to replace NAFTA.

Saying that he was “not playing games,” Trump threatened to close the southern border–including trade–if Mexico did not halt the flow of undocumented immigrants.

“I talked to Democrats and Republicans, they’re also worried that this could exacerbate problems with the USMCA, the trade agreement that they’re trying to finalize that’s already in serious trouble in Congress right now,” said Kelsey Snell, NPR congressional reporter. “They are worried that they’re not going to be able to get the kind of support they need if the President is starting another fight with Mexico. And, you know, there are plenty of people on both sides of the aisle who would really like to get some sort of trade stability happening with both Mexico and Canada.”

Rather than sound belligerent, Trump and his administration should focus more on the humanitarian factors at the border, according to Sen. Dick Durbin (D-Ill.)

“Instead of building fences two or three years in the future by taking money from the Department of Defense, focus on facilities to serve the families so there aren’t children who are hurt and dying as a result of this situation,” Durbin said. “Then look at the big picture. When the president says he’s going to close the border, that is a totally unrealistic best on his part.

“What we need to do is focus on what’s happening in Central America where three countries are disassembling before our eyes and people are coming desperately to the United States. The president’s cutting off aid to these countries will not solve that problem,” Durbin added.

While he said he sympathizes with Trump’s position, former Republican senator and presidential candidate Rick Santorum also believes closing the border would be a mistake.

“I think the idea of closing the border is a bad idea,” Santorum said. “I understand why the president is doing it. He’s upset with Mexico. He has every reason to be upset with Mexico. Mexico could solve this problem. The people that are coming over, that are flooding, that are creating this crisis at the border are not Mexicans. … Mexico is letting people from Honduras and El Salvador and Guatemala come through their country stacking up at the border, not controlling any kind of flow of immigration.”

Trump himself is really to blame for creating the crisis, said Rep. Juan Vargas (D-Calif.).

“No, in fact he’s creating this crisis interestingly,” Vargas said. “We’ve seen numbers larger than this a decade ago, and why were we able to handle it? The administration was trying to handle it. He’s trying to make this crisis, he’s making it a crisis and every time he opens his mouth in Central America they hear, ‘Oh, United States let’s go.’ He is, in a sense, getting more people to come.

“So all the things he’s doing as barbaric as they are, [are] actually making the situation worse,” he added. “I’ve lived on the border my entire life, I have to tell you, it’s never been like this, we’ve had larger numbers, absolutely we’ve had more people coming. But it’s worked better because the administration hasn’t been trying to make it a crisis. They’ve been trying to make it a crisis, trying to make it look bad.”