Mick Mulvaney speaks in the Brady press briefing room at the White House in Washington, March 22, 2018. Credit: Manuel Balce Ceneta | AP

WASHINGTON — Acting White House chief of staff Mick Mulvaney on Wednesday criticized Republicans on the Senate Intelligence Committee for not informing him that President Donald Trump’s son Donald Trump Jr. would be subpoenaed by the panel as part of its ongoing probe into Russian interference in the 2016 campaign.

In an interview with CBS News, Mulvaney said it was “bad form” for the Republican-led committee to subpoena Trump Jr. without giving him advance notice.

“I have no difficulty with bipartisanship, but to subpoena the president of the United States’ son and not at least get a heads-up, I thought was — let’s say bad form,” Mulvaney said.

The Intelligence Committee is seeking additional closed-door testimony by Trump Jr., who has been a focus of several probes — including special counsel Robert Mueller’s investigation — over his involvement in a June 2016 meeting at Trump Tower with a Russian lawyer who allegedly had promised incriminating information about Democratic presidential candidate Hillary Clinton.

Congressional Democrats think that in his previous appearances on Capitol Hill, Trump Jr. may have lied to investigators about that meeting and whether he alerted his father that it would take place.

As negotiations over Trump Jr.’s testimony continued, Senate Intelligence Committee Chairman Richard Burr, R-North Carolina, became increasingly frustrated and believed that Trump Jr. was defying the committee’s authority and not honoring his original agreement, a person familiar with the matter said.

Mulvaney said in Wednesday’s CBS interview that while he was not told that Trump Jr. would be subpoenaed, he did not know whether others in the White House had been informed.

“Possible, but unlikely,” Mulvaney said, adding: “I’m not involved in the president’s — his legal matters regarding his business, his legal matters regarding his family, I don’t do that. I handle the West Wing of the government.”

Most Republicans this week have rallied behind the president’s effort to quash the lingering investigations raised by Mueller’s report, with Senate Majority Leader Mitch McConnell, R-Kentucky, on Tuesday declaring, “Case closed.”

But the Senate Intelligence Committee so far appears to have escaped pressure to end its probe.

Mulvaney on Wednesday claimed that what McConnell’s statement “was speaking to was that the president has been exonerated,” a false claim that the White House repeatedly has made in the wake of the Mueller report’s release.

Mueller declined to say one way or the other whether Trump should have been charged, citing long-standing Justice Department guidance that sitting presidents cannot be indicted. This week, more than 450 former federal prosecutors who worked in both Democratic and Republican administrations signed a statement asserting that Trump would have been charged with obstruction if he were not president.

In the CBS News interview, Mulvaney also insisted that while the president and his son “do share the same name,” they are “two different people,” in an apparent effort to put distance between the two.

“There was no collusion and no obstruction, period, end of story,” he said. “Now it’s time to move on to the business of government. Does that mean that other individuals may or may have not done other things? I have no idea, but I think that’s what Mr. McConnell was speaking to, the implications for the president of the United States.”

He added: “There was no reason that McConnell would go to the floor to talk about Don Jr. That’s just not going to happen. He was talking about the president.”

Washington Post writers Ashley Parker and Matt Zapotosky contributed to this report.