The Trump White House is refusing to give congressional investigators documents relating to payments between Russian entities and former National Security Adviser Michael Flynn, which he failed to disclose — a failure Republican Rep. Jason Chaffetz, chair of the House Oversight Committee, said was "inappropriate" and "a violation of law."

The Trump White House is refusing to turn over documents vital to ongoing probes of Russian interference in the presidential election.

The House Oversight Committee received classified documents from the Defense Intelligence Agency detailing payments former National Security Adviser Michael Flynn received from Russian entities. The documents were turned over as part of the investigation into Flynn’s failure to disclose that money on forms he filled out for his security clearance.

Flynn received over $45,000 for a speech to RT, the state-owned Russian television network, and also made $530,000 from work that his lobbying firm did that benefitted the Republic of Turkey.

In a letter, the White House said it will not give the committee documents it requested about those payments to Flynn. Marc T. Short, White House director of Legislative Affairs, asserts in the letter that it is “unclear how such documents would be relevant” to the review of Flynn’s records.

Rep. Elijah Cummings, the ranking Democratic member of the Oversight Committee, said in a statement the payments are “are extremely troubling” and that he has “grave concerns” about them. He added, “I believe these documents should be declassified to the fullest extent possible without compromising sources or methods.”

Rep. Jason Chaffetz (R-UT), the chairman of the committee, said in a press conference that Flynn failure to disclose receipt of the Russian money was “inappropriate, and there are repercussions for the violation of law.”

CHAFFETZ: If that money was received by General Flynn, and we believe that it was, that money needs to be recovered. That final determination, again will have to come from the Department of the Army, as well as the Department of Defense, but as a former military officer you simply cannot take money from Russia, Turkey, or anybody else. And it appears as if he did take that money, it was inappropriate, and there are repercussions for the violation of law.

Flynn was removed from the Trump administration after it was discovered he had lied about his contact with Russians. But since then, Trump has defended Flynn as his administration has been battered by a series of revelations about his campaign’s contact with Russia.

These developments come as details of the Senate investigation into Russian interference reveal that that committee’s failure under Senator Richard Burr (R-NC) to subpoena witnesses or appoint a full-time staff to investigate the slate of issues relevant to the probe.

Disgust with the congressional approach to this investigation has pushed demand for an independent probe, and in a recent poll, 73 percent of respondents supported one. No matter how hard the White House and congressional Republicans try to hide the truth about the Trump campaign’s involvement with Russia, Americans are not going to stop demanding answers.