Special counsel Robert Mueller departs after a meeting on Capitol Hill in Washington, June 21, 2017. Credit: J. Scott Applewhite | AP

Rep. Adam Schiff, D-California, said Sunday that House Democrats will subpoena special counsel Robert Mueller III to testify before Congress if his report on Russian interference in the 2016 campaign is not made public.

Schiff, chairman of the House Intelligence Committee, said on ABC News’ “This Week” that Democrats will also subpoena Mueller’s report and are prepared to go to court against the Trump administration.

With Mueller’s nearly two-year investigation believed to be coming to an end, Democrats are seeking to ramp up pressure on Attorney General William Barr to release the full findings of the report — and setting down a marker for what course they will take if he doesn’t.

“Well, we will obviously subpoena the report. We will bring Bob Mueller in to testify before Congress. We will take it to court if necessary,” Schiff said. “And in the end, I think the Department [of Justice] understands they’re going to have to make this public. I think [Attorney General William] Barr will ultimately understand that, as well.”

“During his confirmation hearing last month, Barr said his goal would be to “provide as much transparency as I can consistent with the law.” His testimony prompted concern among Democrats that he could choose not to release any of the findings of Mueller’s team that have not already been made public through indictments.

[Sarah Sanders says White House remains confident about upcoming special counsel report]

Rumors swirled last week that the report could be delivered before the end of the month. But a senior Justice Department official said Friday that the report will not be coming this week.

Justice Department regulations call for Mueller’s report to be a confidential account of the individuals charged, as well as those who were not charged. Barr, who was confirmed earlier this month, will then summarize the work for Congress.

Schiff also took aim at Barr, saying that if the new attorney general withholds any part of the report, his legacy will be “tarnished.” Ultimately, the Democratic lawmaker added, President Donald Trump should welcome the report’s release, given his repeated claims that there was no collusion between his campaign and the Russian government.

“We are going to share this information with the public, and if the president is serious about all of his claims of exoneration, then he should welcome the publication of this report,” Schiff said.

Other Democrats echoed Schiff’s pledge to take action.

“If the attorney general takes the Mueller report and then sanitizes it and releases that as the answer to a comprehensive investigation, then I think the Democrats in the House and Senate — along with Republicans — have a responsibility to ensure that the American people know what happened in 2016,” Sen. Edward Markey, D-Massachusetts, said in an interview on CBS News’ “Face the Nation.”

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Some have viewed Barr’s criticism of former FBI director James Comey during last month’s hearing as an indication of how he might handle the Mueller report. Barr argued that Comey was wrong to have announced during the 2016 campaign that former Secretary of State Hillary Clinton would not be charged for her use of a private email server.

“If you’re not going to indict someone, you don’t stand up there and unload negative information about the person,” Barr said at the time. His remarks stoked speculation that he might be inclined to keep secret all or part of the Mueller report, depending on its findings.

Opinions on whether Democrats would be able to successfully subpoena Mueller were split on Sunday.

In an appearance on NBC News’ “Meet the Press,” Neal Katyal, who was acting solicitor general in the Obama administration, said it was “certainly possible” that Mueller would testify before Congress.

If Mueller ends up finding information that points to potential wrongdoing by the president, Barr not only has the discretion to turn the report over to Congress, “indeed, he has to,” said Katyal, who drafted the special counsel regulations.

“The overall intent of the regulations — it’s said time and time again — is public confidence in the administration of justice. And any sort of suppressed report about presidential wrongdoing will flunk that test,” he said.

On CBS News’ “Face the Nation,” Sen. Roy Blunt, R-Missouri, voiced uncertainty about whether Democrats could enforce a subpoena against Mueller.

“I don’t know that you can,” he told host Margaret Brennan.

Blunt also declined to say whether the Senate Intelligence Committee, of which he is a member, may pursue its own effort to have Mueller testify.”I think we’ll have to wait and see what’s in the report,” he said.

If Trump asks Barr to let him read the report, that is “perfectly fine,” said Solomon Wisenberg, who was deputy independent counsel in the probe of President Bill Clinton.

But the problem will be if Trump orders Barr to take a certain action on the report, Wisenberg said on “Meet the Press.”

“I don’t think Barr will stand for that,” Wisenberg said.

Washington Post writers Peter Holley, Devlin Barrett and Karoun Demirjian contributed to this report.