Cicilline said earlier on "Fox News Sunday" that the House Judiciary Committee had come to a tentative date of May 15 for Mueller testify, noting that a representative for the special counsel had agreed to the date but "obviously, until the day comes, we never have an absolute guarantee." "A tentative date has been set of May 15th and we hope the special counsel will appear," Cicilline said. "We think the American people have a right to hear directly from him."

The Justice Department declined to comment to The Hill, and a request for comment from Mueller's former spokesman was not immediately returned.

"The White House has so far indicated they would not interfere with Mr. Mueller's attempts to testify, we hope that won't change," Cicilline said on Fox News.