A frustrated Mueller told AG Barr his short summary of the special counsel report caused confusion

Justice Department officials described the conversation between the men. The contents of Mueller’s letter to Barr were first reported by the Washington Post.

The officials said Mueller did not describe Barr’s letter as inaccurate but that he thought it was resulting in misleading news coverage about the report.

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“He expressed frustration over the lack of context and the resulting media coverage regarding the special counsel’s obstruction analysis,” a Department of Justice spokeswoman said.

Barr has said he did not want to put the report out piecemeal and could not simply release the summaries because they had not yet been scrubbed to remove grand jury information. Each page of the document, including the summaries, was marked, “May Contain Material Protected Under Fed. R. Crim. Prod. 6(e),” a reference to a rule of federal criminal procedure that bars public disclosure of grand jury information.

Senior department officials were described as frustrated that the report did not contain proposed redactions to protect that material and other categories of information.

Barr’s letter to Congress, made public at the time, said the Mueller investigation “did not establish that members of the Trump Campaign conspired or coordinated with the Russian government in its election interference activities.” It also said the special counsel investigation “did not draw a conclusion — one way or the other —as to whether the examined conduct constituted obstruction.”

Mueller sent his letter to Barr three days later, saying the resulting confusion threatened to undermine public confidence in the investigation. Justice Department officials said they were surprised by the tone of the letter, but said Mueller was less pointed in their subsequent phone call.

They said Barr also repeated that his letter was not intended to be a summary of the report. The department spokeswoman described the phone call as “cordial and professional.”

Members of Mueller’s team have previously expressed frustration that Barr cleared Trump of obstruction of justice in his summary letter in March. A U.S. official who spoke with the members of Mueller’s team told NBC News early this month that they believed the evidence that Trump sought to impede the investigation was stronger than Barr suggested.

A senior law enforcement official who also has spoken to members of Mueller’s team told NBC News this month that they say the report includes detailed accounts of contacts between Trump’s campaign and Russia.

Barr told reporters two weeks ago that there were 10 potential “episodes” of obstruction of justice by Trump but that they didn’t amount to illegal activity. But he acknowledged that he disagreed with some of Mueller’s legal theories on whether those episodes amounted to obstruction “as a matter of law.”

Barr — who expressed skepticism about Mueller’s investigation before Trump made him attorney general — testified before a Senate committee this month that the investigation may have involved inappropriate surveillance of the Trump campaign. He said he would conduct a review of the matter.

Trump and congressional Republicans argue that the Russia investigation was the work of biased FBI leaders who bore ill will toward Trump, including former Director James Comey and former Acting Director Andrew McCabe, who was deputy director at the time. Both men have denied that they acted out of any bias.

Pete Williams

Pete Williams is an NBC News correspondent who covers the Justice Department and the Supreme Court, based in Washington.

Alex Johnson contributed.