First on Fox: Sen. Roger Marshall, R-Kan., is doubling down on a contentious tussle with Dr. Anthony Fauci on Tuesday by once again requesting, this time in the form of a letter, the top White House medical adviser provide financial disclosure forms.

"On Tuesday, I asked if you would provide your financial disclosures and investments to Congress and the public," Marshall, a physician and military veteran, wrote to Fauci in a letter obtained by Fox News. "As a member of the committee directly responsible for the oversight of NIAID, I expect a direct, transparent, and honest answer. Instead I was met with a personal insult, deflection, and counter question as to why financial disclosures are important. At a time when multiple federal officials have stepped down due to questionable financial transactions during the pandemic, these questions are both reasonable and relevant."

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Fauci and Marshall sparred on Capitol Hill Tuesday when the senator asked about Fauci’s financial interests. 

"As the highest-paid employee in the entire federal government," Marshall asked.  "Yes or no, would you be willing to submit to Congress and the public a financial disclosure that includes your past and current investments?"

Fauci COVID Sen. Marshall

Dr. Anthony Fauci  listens during a meeting with the White House COVID-19 Response Team on the latest developments related to the omicron variant on the White House campus on Jan. 4, 2022. (AP Photo/Andrew Harnik)

Fauci responded, "I don't understand why you're asking me that question. My financial disclosure is public knowledge and has been so for the last 37 years or so, 35 years."

After the two continued to go back and forth, Fauci was caught on a hot mic disparaging the senator.

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"What a moron, Jesus Christ!" an exasperated Fauci could be heard saying.

In the letter to Fauci, Marshall cites a New York Post article in which a Fauci spokesperson was unable to produce the disclosures that Fauci claimed were public and a Forbes article reporting that Fauci’s salary, stock and bond purchases, and royalty payments for this year and last year are not publicly available.

Sen. Roger Marshall departs a meeting at the U.S. Capitol in Washington on Dec. 1, 2021. (REUTERS/Elizabeth Frantz)

Sen. Roger Marshall departs a meeting at the U.S. Capitol in Washington on Dec. 1, 2021. (REUTERS/Elizabeth Frantz)

"This letter is to formally request your financial disclosures for the fiscal years covering the pandemic," Marshall wrote. "Several of my requests for information from your office have required months for a response or are still outstanding. Please provide these disclosures by 5:00pm Friday, January 14. Furthermore, considering the extensive redaction of the disclosure dated April 21, 2020, please provide me with copies that only redacts personal and sensitive information allowed for by law."

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Fauci's NIAID gave the following statement to Fox News: "Dr. Fauci and all directors of NIH Institutes and Centers are public report filers due to the responsibilities of their positions pursuant to the last criteria listed in 5 CFR 2634.202(c): "and each officer or employee in any other position determined by the Director of the Office of Government Ethics to be of equal classification."