House Democrats demand subpoena for Michael Flynn's White House records They expect to find “egregious conflicts of interest” in his overseas dealings.

 -- House Democrats are calling on their Republican colleagues to subpoena the White House for documents concerning foreign contacts made by former national security adviser Michael Flynn, which they believe could show “egregious conflicts of interest” in Flynn’s overseas business relationships.

“We believe this paper trail must be pursued to answer the gravest question of all – Did General Flynn seek to change the course of our country’s national security to benefit the same private interests he previously promoted, whether by advising President Trump, interacting with foreign officials, or influencing other members of the Trump administration?” said Ranking House Oversight Committee Member Elijah Cummings, D-Md., in a letter to Chairman Trey Gowdy, R-S.C., cosigned by 18 Democratic members.

The 10-page letter, a lays out for Gowdy the arguments for using the committee’s oversight authority to compel the White House to turn over records related to Flynn’s foreign contacts and security clearance – documents first requested in March after the panel learned Flynn was paid more than $56,000 by Russian companies in 2015. The White House declined in an April letter to provide any information on Flynn and said it didn’t possess any records related to his transition activities.

A full copy of the letter can be read below.

Flynn, a retired Army lieutenant general, was forced out of his job as Trump’s national security adviser after just 24 days for misleading Vice President Mike Pence about conversations with Russian officials during the transition.

Flynn’s attorney, Robert Kelner, has declined repeated requests for comments about his client’s business dealings. A source close to Flynn told ABC News the retired lieutenant general “has already produced a large volume of documents in response to extensive subpoenas from the House and Senate Intelligence Committees.”

Democrats believe Flynn concealed foreign contacts and overseas trips in his application to renew his security clearance, in financial disclosure reports and in interviews with Pentagon officials.

Congressional investigators documented Flynn’s travel to the Middle East in June 2015 and said Flynn failed to mention those trips on his security clearance renewal application the following year as required. Cummings said Flynn later failed to disclose the trip and subsequent foreign contacts during interviews with security clearance investigators as part of the background check process.

Further, the committee cited news accounts that have documented Flynn’s work with several companies to promote a joint U.S.-Russia partnership to develop nuclear power plants in the Middle East, with financing from Saudi Arabia. Flynn’s disclosure forms say his 18-month engagement on the project ended in December 2016. But a Wall Street Journal report suggested that even after Flynn worked privately pursuing such a venture, he continued to promote the concept inside the White House from his senior national security post.

“If General Flynn was communicating about a multi-billion-dollar Saudi Arabian nuclear project from inside the White House,” the House Democrats said in their letter Tuesday, “he may have violated federal laws that protect against egregious conflicts of interest, as well as President Trump’s own ethics pledge.”

When reached for comment, a representative from Gowdy’s office told ABC News that special counsel Robert Mueller and his team are handling any investigation into any alleged criminal activity.

“Any alleged criminal or quasi criminal actions fall under the jurisdiction of Special Counsel Mueller,” a committee spokesperson said. “The Committee will not do anything to interfere with the Special Counsel’s probe.”

The Democrats have also asked Gowdy to issue subpoenas to three private companies that pursued the nuclear power project in the Middle East. Flynn advised all three companies but didn’t disclose any contacts with foreign officials about the project on his security clearance forms, according to Democrats.

“The information regarding what General Flynn disclosed to the White House regarding his foreign contacts is critical to this Committee’s understanding of his actions as National Security Advisor, his risk to our country’s national security, and the security clearance process at the White House,” they wrote.

Flynn, who has remained a focus of the ongoing special counsel and congressional Russia investigations, invoked his Fifth Amendment rights in response to a Senate Intelligence Committee subpoena in May.