House Judiciary Committee chair Rep. Jerry Nadler (D-NY) signaled late Thursday that he had delayed filing a lawsuit seeking to force former White House Counsel Don McGahn to comply with a Congressional subpoena until next week.

Calling McGahn “the main fact witness” of former special counsel Robert Mueller’s report, Nadler told CNN’s Anderson Cooper that a lawsuit to enforce a subpoena for McGahn’s testimony would be filed early next week.

“You have to lay out the facts to the American people and it is very frustrating that the administration has systematically attacked the right of Congress to hold any administration accountable — opposed all our subpoenas and we have to break that log-jam in order to lay out the facts before the American people,” he said.

Nadler had said on Wednesday that the McGahn lawsuit would be filed by the end of this week.

The Judiciary Committee chair said on his Thursday CNN appearance that the House would likely file a separate lawsuit on Friday, seeking to compel the release of sealed grand jury materials from the Mueller investigation.

Nadler framed the lawsuits as the start of a volley of attempts to conduct proactive and vigorous oversight of the Trump administration, after mounting criticism and angst that the Democrats have moved too slowly on investigating the executive branch.

“Our next step starting tomorrow is to get the evidence before the American people,” Nadler said, referring to questions about information from the Mueller investigation.

Nadler subpoenaed McGahn in April, seeking reams of documents from the former White House counsel as well as his testimony.

McGahn played a leading role in the obstruction volume of the Mueller report, threatening to resign rather than order Mueller’s firing and later refusing to deny news reports about Trump’s demand to do so.

Since Nadler issued the subpoena, the White House has maneuvered to keep McGahn out of Congress’s hands. In May, the Justice Department issued a legal opinion contending that Congress could not compel McGahn’s testimony, while the White House directly ordered McGahn not to comply with the documentary subpoena.

On his Thursday CNN appearance, Nadler put aside questions about whether his committee would open an impeachment inquiry, saying instead that Congress needed to make the case first by obtaining McGahn’s testimony.

“When we’ve laid out the facts in front of the American people, then we’ll proceed,” he said.