Rep. Adam Schiff said Sunday that President Trump and his legal team are “terrified” at what Paul Manafort could tell special counsel Robert Mueller.

"They may think they know what Manafort has to say, because he was part of that joint defense agreement, but they have to know that he may not have told them the full truth," Schiff, the top Democrat on the House Intelligence Committee, said on NBC's "Meet the Press."

The California Democrat added: ”They’re terrified of what he has to say. I’m surprised that we are where we are, that Manafort is cooperating."

Manafort, the former Trump campaign chairman, pleaded guilty on Friday to two federal charges, while reaching a deal to cooperate with special counsel Robert Mueller. Manafort was also convicted last month in Virginia on bank and tax fraud charges brought against him by Mueller.

Schiff said the plea deal “sends a message” to anyone else Mueller is targeting.

"This sends a message to anyone who is in Bob Mueller's crosshairs right now: You better get to the special counsel and make your deal now, because anyone that gets indicted by Bob Mueller goes down,” Schiff said. “The longer you wait to come clean, the worse deal you are going to get."

[Alan Dershowitz: Manafort plea a ‘big win’ for Mueller]

Trump has continued to take aim at the special counsel’s investigation, even tweeting on Sunday on what he has continually dubbed “a witch hunt.” He and the White House have sought to downplay the Manafort plea deal.

Manafort is part of a handful of incidents central to Mueller’s investigation, including the now-infamous 2016 meeting at Trump Tower predicated on a Russian lawyer promised “dirt” on Hillary Clinton.

“We want to know: What can Manafort tell us about whether any of that was consummated? He's trying to get money, they're trying to get dirt, the Russians are trying to help Trump. Was there a meeting of the minds?” Schiff remarked. “Manafort is a key person to help us unwind whether this is the most improbable string of unlikely coincidences, or whether this was an act of conspiracy.”

Former Harvard law professor Alan Dershowitz told “Meet the Press” earlier Sunday that Manafort’s deal represents a “very bad day for the Trump administration.”