House Judiciary Committee Chairman Jerrold Nadler (D-N.Y.) on Tuesday said Attorney General William Barr “must answer” for reports that special counsel Robert Mueller objected to Barr’s summarization of the conclusions in the investigation into Russia’s election interference.

Nadler’s comment comes after The Washington Post reported that Mueller sent Barr a letter in late March expressing concern that Barr did not “fully capture the context, nature, and substance” of the special counsel’s probe.

“I have demanded the letter & Barr must answer for this. Mueller must be allowed to testify,” Nadler tweeted shortly after the Post published its report, which comes two days before Barr is slated to testify before Congress.

Mueller has written a letter objecting to Barr’s summary of his report because it “did not fully capture the context, nature and substance of the investigation.” I have demanded the letter & Barr must answer for this. Mueller must be allowed to testify. https://t.co/gylocOsYlv

— (((Rep. Nadler))) (@RepJerryNadler) April 30, 2019

{mosads}Mueller reportedly sent the letter to Barr on March 27, shortly after the attorney general sent a memo to lawmakers stating the special counsel didn’t find evidence of coordination between President Trump’s 2016 campaign and Russia.

In the letter, Mueller reportedly argues that Barr “did not fully capture the context, nature, and substance of this office’s work and conclusions” in his description of the report’s conclusions.

“There is now public confusion about critical aspects of the results of our investigation. This threatens to undermine a central purpose for which the Department appointed the Special Counsel: to assure full public confidence in the outcome of the investigations,” he wrote, according to the letter obtained by The Washington Post, which called on Barr to release the introductions and executive summaries in the report.

Top Democrats have been highly critical of Barr’s handling of the Mueller report, which was more than 400 pages, alleging he was highly partisan while presenting the findings of the investigation.

Nadler issued a formal request for Mueller to testify earlier this month, echoing the calls of Speaker Nancy Pelosi (D-Calif.) and Senate Minority Leader Charles Schumer (D-N.Y.).

Barr is scheduled to testify before the House Judiciary Committee on Thursday, but it remains unclear whether he will show up due to objections over Democrats’ call to allow for a half hour of questioning from committee lawyers in addition to being grilled by the panel’s lawmakers.