White House press secretary Sarah Huckabee Sanders suggested Tuesday that President Donald Trump may well try to block special counsel Robert Mueller from testifying before Congress.

Speaking on ABC’s podcast “The Investigation,” Sanders put some additional weight behind Trump’s tweets this weekend in which he said, in no uncertain terms, “Bob Mueller should not testify.”

“I think that’s a determination to be made,” she said. “At this point, I think it’s the president’s ... that’s the president’s feeling on the matter, and the reason is because we consider this as a case closed, as a finished process.”

Trump’s tweets reportedly caught his own inner circle off guard, contradicting as they did Attorney General William Barr’s statements on the matter.

As Politico reports, if Mueller is still on the Justice Department payroll, Trump could conceivably limit his testimony by invoking executive privilege. But the department doesn’t have nearly as much sway over a private citizen, former Obama Justice Department spokesman Matt Miller told Politico.

“I know of no instance where the department has been able to affirmatively restrain anyone from executing their First Amendment rights,” Miller said, “especially if they were responding to a lawful subpoena.”