The Department of Justice told former special counsel Robert Mueller that he must restrict his testimony to two House panels to the contents of his report on Russian influence in the 2016 election, according to a report.

“Any testimony must remain within the boundaries of your public report because matters within the scope of your investigation were covered by executive privilege, including information protected by law enforcement, deliberative process, attorney work product, and presidential communications privileges,” Associate Deputy Attorney General Bradley Weinsheimer wrote in a letter to Mueller obtained by The Hill on Monday.

Weinsheimer said he was responding to a July 10 letter from Mueller seeking guidance from the department “concerning privilege or other legal bars” involving his testimony.

Mueller will appear before the House Judiciary and Intelligence committees on Wednesday.

He issued his 448-page report in March and Attorney General William Barr released a highly redacted version of it weeks later.

Weinsheimer re-emphasized that Mueller should not discuss the redacted portions of the report because they contain grand jury testimony and information about ongoing investigations.

A spokesman for the former special counsel, Jim Popkin, said Mueller has been getting ready for his appearance.

“If you look at him and his career, he is someone who comes to the table fully prepared and he’s going to be ready on Wednesday,” Popkin told The Hill.

But Mueller is a reluctant witness.

In his last public comments in May, Mueller said, “The report is my testimony.”

“There has been discussion about an appearance before Congress. Any testimony from this office would not go beyond our report,” he said.