(Bloomberg) — Talks to avert a second government shutdown over border wall funding broke down on Saturday, and Republicans and Democrats have stopped communicating for now, according to two people familiar with the state of the talks.

The latest sticking point appears to be over detention beds operated by the U.S. Immigration and Customs Enforcement, the person said.

Mick Mulvaney, the acting White House chief of staff, said Sunday that a shutdown isn’t the most likely option but that he “absolutely cannot” rule it out.“He’s going to do whatever he legally can to secure the border,” Mulvaney said of President Donald Trump on NBC’s “Meet the Press,” one of two scheduled appearances on Sunday talk shows.

“You cannot take a shutdown off the table, and you cannot take $5.7 (billion) off the table,” he said, referring to the level of funds Trump has been demanding for a wall on the U.S.-Mexican border.

Mulvaney spoke as Congressional negotiators continue talks on a security plan that includes some sort of barrier on the border, hoping to complete a deal to avert another government shutdown. It wasn’t fair to say that Trump would sign whatever Congress comes up with, Mulvaney said, terming the level of proposed border wall funding “all over the map.”

As of Saturday it seemed that negotiators were homing in on a proposal with border barrier funding of between $1.3 billion and $2 billion, said a person familiar with the talks.

Trump was back in the fray late Saturday afternoon, indicating in a tweet that if Democrats didn’t give him all the wall money he’s demanded, he may use executive action to build it. Democrats have warned such action would face court challenges, and some Republicans have suggested it’s an option best avoided.

To contact the reporters on this story: Ros Krasny in Washington at rkrasny1@bloomberg.net;Erik Wasson in Washington at ewasson@bloomberg.net

To contact the editors responsible for this story: James Ludden at jludden@bloomberg.net, Ros Krasny

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