Then-White House counsel Don McGahn at a Cabinet meeting in the White House in October 2018. (AP file photo/Evan Vucci)

WASHINGTON (CN) – Don McGahn, the former White House counsel portrayed in the Mueller report as refusing pressure from President Donald Trump to influence the investigation, will not comply with a congressional subpoena, a White House lawyer said Tuesday.

“The White House records remain legally protected from disclosure under longstanding constitutional principles, because they implicate significant executive branch confidentiality interests and executive privilege,” White House counsel Pat Cipollone wrote in a letter to Representative Jerry Nadler, a Democrat who chairs the House Judiciary Committee.

Nadler subpoenaed McGahn in April, asking him to turn over a trove of White House documents related to the Mueller probe. McGahn was a key figure in the section of Mueller’s report devoted to potential obstruction by Trump, most notably when he threatened to resign rather than follow through with Trump’s instruction to have Mueller fired.

Under the subpoena, McGahn had until Tuesday to comply with the subpoena. The committee’s subpoena also asked him to testify publicly later this month.

White House Press Secretary Sarah Sanders hinted earlier Tuesday that Nadler would be refused by the White House, telling “The Investigation” podcast by ABC News that Democrats should move on from Mueller’s probe and the allegations of a conspiracy between the Russian government and the Trump campaign.

In his report, Mueller cleared the Trump campaign of criminally conspiring with the Russian government, but did not make a decision on whether Trump obstructed justice.

Senate Majority Leader Mitch McConnell, R-Ky., said Tuesday the report means it is “case closed” on allegations of collusion between the Trump campaign and Russia. He said Democrats who continue to focus on the investigation, including by accusing Attorney General William Barr of misrepresenting its findings, are attempting to delay coming to grips with the results of the election.

“So remember, Russia set out to sow discord, to create chaos in American politics and undermine confidence in our democracy,” McConnell said. “But on that front, given the left’s total fixation on delegitimizing the president, the president Americans chose, and shooting any messenger who tells them inconvenient truths, I’m afraid the Russians hardly need to lift a finger.”

McConnell also jabbed at President Barack Obama for his comments in the 2012 campaign that downplayed the threat from Russia, recalling Obama’s quip that “the 1980s are now calling to ask for their foreign policy back.”

A day earlier, the House Judiciary Committee revealed plans for a vote to hold Barr in contempt for his failure to turn over an unredacted version of Mueller’s report in response to a committee subpoena.

Senate Minority Leader Chuck Schumer, D-N.Y., responded to McConnell’s remarks by accusing Republicans of trying to ignore issues with election security and of eliding key findings in Mueller’s report.

“If the leader is sincere, then put election security on the floor,” Schumer said, referring to McConnell. “Let’s debate it. Put sanctions on Russia on the floor. Let’s debate it. He doesn’t want to move on. He wants to run away from these awful facts that related to the wellspring of our democracy.”