House Democratic leaders on Tuesday formally called for President Trump’s removal from office, asserting that he “ignored and injured the interests of the nation” in two articles of impeachment that charged him with abusing his power and obstructing Congress.

The Justice Department, after weeks of tense negotiations, has agreed to provide Congress with key evidence collected by Robert S. Mueller III that could shed light on possible obstruction of justice and abuse of power by President Trump, the House Judiciary Committee said on Monday.

Donald F. McGahn II, the former White House counsel, defied a House subpoena on Tuesday under order of the White House, stoking outraged Democrats to contemplate anew punitive measures, including opening an impeachment inquiry, to try to enforce Congress’s oversight powers.

President Trump asserted executive privilege on Wednesday in an effort to shield hidden portions of Robert S. Mueller III’s unredacted report and the evidence he collected from Congress. The assertion, Mr. Trump’s first use of the secrecy powers as president, came as the House Judiciary Committee is expected to vote Wednesday morning to recommend the House of Representatives hold Attorney General William P. Barr in contempt of Congress for defying a subpoena for the same material.