Former Democratic National Committee chairman Howard Dean claimed Sunday on MSNBC that President Donald Trump is “mentally incapacitated” and, therefore, cannot negotiate an agreement to end the partial shutdown of the federal government.

“I actually think the president is mentally incapacitated, and I have thought so for quite some time,” said Dean. “He says things that he knows aren’t true, I suspect, and that, somehow, he thinks that people are going to believe. And they just don’t.”

“You can’t really make a bargain with somebody who is irrational because they won’t keep it,” the one-time failed presidential candidate continued. “The Republicans and the Democrats in Congress have got to do the best they can to run this country in the absence of the chief executive. Until the Republicans realize they have an obligation to the country, not just their party, that’s not going to happen.”

With 2019 just hours away, a resolution to the government shutdown, which went into effect December 22, does not appear to be tenable with Democrat leaders Rep. Nancy Pelosi (D-CA) and Sen. Chuck Schumer (D-NY). President Trump is holding out on a deal to secure $5 billion in funding to construct a wall on the U.S.-Mexico border.

On Monday morning, President Trump once again reaffirmed his commitment to fulfill his chief campaign promise to build the wall. “I campaigned on Border Security, which you cannot have without a strong and powerful Wall,” the president tweeted. “Our Southern Border has long been an ‘Open Wound,’ where drugs, criminals (including human traffickers) and illegals would pour into our Country. Dems should get back here and fix now!”