White House acting chief of staff Mick Mulvaney said Sunday that, whatever Congress may or may not propose in a border security compromise, President Donald Trump will get his wall on the U.S.-Mexico border.

"The president is going to build the wall," Mulvaney said on "Fox News Sunday." "This is going to get built with or without Congress."

Mulvaney's words come as another potential government shutdown looms. Lawmakers have until Friday to craft a deal that the president would sign on to.

The negotiations hit a roadblock Sunday when Democrats pushed to limit the number of migrants that the Immigration and Customs Enforcement agency can detain at one time. Many Democrats have criticized ICE for going too far in detaining immigrants who lack proper documentation but are otherwise lawful and some have advocated getting rid of the agency altogether.

Republicans have called the push to abolish ICE evidence that Democrats are for "open borders" and do not really wish to stop illegal immigration. They say ICE is essential in enforcing current U.S. immigration law.

"I don’t think the Dems on the Border Committee are being allowed by their leaders to make a deal," Trump tweeted Sunday in response to the Democratic proposal to limit the number of ICE detainees. "They are offering very little money for the desperately needed Border Wall & now, out of the blue, want a cap on convicted violent felons to be held in detention!"

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Democrats say they proposed their cap to force ICE to concentrate its internal enforcement efforts on dangerous immigrants. Democrats have proposed reducing the current number of beds ICE uses to detain immigrants here illegally from 40,520 to 35,520. But within that limit, they want most of the beds used for people detained at the border and proposed limiting the number of beds for immigrants here illegally who are caught within the U.S. to 16,500.

"I promise you this. Donald Trump is not going to sign any bill that reduces the number of bed spaces available to hold violent offenders who come across our border. He can't do that. He won't do that," Sen. Lindsey Graham, R-S.C., said on Fox News' "Sunday Morning Futures."

Graham said such a move "incentivizes more violent people to come to the United States" and "at the end of the day, they're making it impossible for the president to work with them if they're reducing bed spaces for violent offenders."

Sen. Richard Shelby, R-Ala., was not optimistic about the chances of reaching an agreement ahead of Friday's deadline.

"I think talks are stalled right now," Shelby told "Fox News Sunday" host Chris Wallace. "I’m not confident we’re going to get there."

On the other side of the aisle, Sen. Jon Tester, D-Mont., told Wallace on Sunday that, "We are not to the point where we can announce a deal."

If lawmakers fail to find common ground and the president is not presented with a bill that he finds acceptable, Trump is prepared to reject it and risk another shutdown, Mulvaney said.

"The government shutdown is technically still on the table," he said. "We do not want it to come to that, but that option is still open to the president and will remain so."

When asked if Trump – who wants $5.7 billion for a border wall – would sign a funding bill that only appropriated between $1.3 and $2 billion for construction, Mulvaney said, "We’ll take as much money as you can give us and then we will go off and find the money someplace else legally."

Congressional Democrats have steadfastly refused to approve the $5.7 billion requested by Trump for the wall, and House Speaker Nancy Pelosi has insisted the wall won't be built. In December, the impasse led to a record 35-day government shutdown.

Mulvaney said Trump could get some of the money without Congressional approval and with declaring a national emergency through "reprogramming," which would permit the president to move around previously allocated defense funds.

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A number of Republican lawmakers, including Senate Majority Leader Mitch McConnell, R-Ky., oppose the idea of declaring a national emergency to get the money because they say it would subvert congressional authority and establish a bad precedent. Despite that opposition, Mulvaney said such a move is "absolutely on the table."

"Yes, there's a lot of Republicans who don't want to do it. Face it, the president doesn't really want to do it. That's why we had to go through the shutdown," Mulvaney said. "He would prefer legislation because it's the right way to go and is the proper way to spend money in this country.

"But if that doesn't happen, the president proceeds. His number one priority is national security. He will then look at the National Emergencies Act as a way to do his job," he added.

Contributing: The Associated Press

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