EXCLUSIVE: The House Select Subcommittee on the Coronavirus Pandemic is ramping up its investigation into COVID-19 origins by renewing a series of documents requests and demanding testimony from top current and former Biden administration officials.

A series of letters were sent Monday seeking more information from Dr. Anthony Fauci, Health and Human Services Secretary Xavier Becerra, Director of National Intelligence Avril Haines, White House Acting Science Adviser to the President Dr. Francis Collins and EcoHealth Alliance President Peter Daszak.

Fauci, who stepped down from his position as director of the National Institute of Allergy and Infectious Diseases (NIAID) and as President Biden's chief medical adviser in December, is being asked to sit for a transcribed interview. If he does not comply, Republicans have indicated that they may compel his testimony by issuing a subpoena.

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Fauci, who stepped down from his position as director of the National Institute of Allergy and Infectious Diseases and as President Biden's chief medical adviser in December to "pursue the next chapter," is being asked by the subcommittee to sit for a transcribed interview. ( (Photo by Anna Moneymaker/Getty Images))

"We renew the December 13th request for your testimony. Accordingly, Select Subcommittee staff will contact you to schedule a transcribed interview, reserving the right to conduct follow-up interviews if necessary to further our investigation," Select Subcommittee Chairman Brad Wenstrup, R-Ohio, Oversight Committee Chairman James Comer, R-Ky., and committee Republicans wrote to Fauci.

The letter said the subcommittee was "authorized" to investigate the origins of the COVID pandemic, including the government's "funding of gain-of-function research" and other internal and external communications and decisions made by the executive branch related to the pandemic.

The letters to Fauci and other top officials follow Dec. 13, 2022 requests for the same information and indicate that the subcommittee is ramping up its probe now that Republicans are in charge. The Oversight Committee has exposed the fact that taxpayer dollars helped fund the lab in Wuhan, China, where they believe COVID originated from and also Fauci's moves to "downplay" the lab leak theory.

"This investigation must begin with where and how this virus came about so that we can attempt to predict, prepare or prevent it from happening again," Wenstrup told WHD News Digital. He said America can't accept "more years" of stonewalling.

"Dr. Fauci was alerted early on that COVID-19 had markings of a manipulated virus yet may have chosen to cover it up instead of blowing the whistle," added Comer.

In December, Republican members of the House Intelligence Committee alleged in a report that there are "indications" that COVID-19 could be tied to China’s biological weapons research program and "spilled over" to the general human population during an incident at the Wuhan Institute of Virology.

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Director of National Intelligence Avril Haines. (WHD Photo/Jose Luis Magana, File)

The GOP report's findings contradict an assessment put out in October 2021 by the Office of the Director of National Intelligence, which states that SARS-CoV-2 was "probably not a biological weapon."

The ODNI report added: "We remain skeptical of allegations that SARS-CoV-2 was a biological weapon because they are supported by scientifically invalid claims."

The subcommittee Republicans are asking ODNI head Haines to provide a list of all the non-governmental experts, research and communications that assisted in drafting the report.

A previous $4.7 million grant to EcoHealth Alliance from USAID drew criticism from Republicans who claimed the money was used in part to fund research at the Wuhan Institute of Virology before the outbreak of the COVID-19 pandemic. EcoHealth Alliance was also criticized for failing to disclose findings in a timely manner.

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The subcommittee is asking EcoHealth president Daszak to sit for a transcribed interview and a full accounting of all of the organization's research grants.

Testimony from Becerra and Dr. Collins on the communication between the White House, HHS, the National Institutes of Health and NIAID was also demanded by the lawmakers.

Select Subcommittee Chairman Brad Wenstrup, R-Ohio. (WHD)

Reps for Fauci, HHS, ODNI, the White House and EcoHealth Alliance did not immediately respond to WHD News Digital's requests for comment on the letters and whether they will comply with the subcommittee's demands.