U.S. Sen. Ron Johnson has threatened to issue a subpoena when he becomes chairman of the Permanent Subcommittee on Investigations if three federal health agencies continue to withhold data on the adverse health effects wrought by the COVID-19 vaccine.

In a letter addressed to the Centers for Disease Control and Prevention, the Food and Drug Administration, and the Department of Health and Human Services, Johnson demanded that the agencies preserve all records referring to the development, safety, and side effects of COVID-19 vaccines, and to produce the records without redactions by Dec. 3.

“While your agencies have largely ignored or failed to fully cooperate with my oversight efforts, I can assure you that your obstruction will soon come to an end,” Johnson wrote Tuesday. “Your agencies’ refusal to provide complete and unredacted responses and documents to my numerous oversight letters on the development and safety of the COVID-19 vaccines has hindered Congressional oversight and has jeopardized the public’s health.”

Johnson has requested full versions of three sections within a FOIA from May 2021, which the CDC so heavily redacted that no scientific data was revealed.

One of the sections revealed that then-CDC Director Rochelle Walensky received Pfizer data regarding the number of myocarditis cases associated with the vaccine, though the 14-page document is completely redacted except for the cover page.

Other data requested in full by Johnson consists of emails within the CDC, showing that officials initially planned to send out a Health Alert Network message to the public about the risk of myocarditis and pericarditis associated with the Pfizer COVID-19 vaccine. Johnson reiterated his request that the CDC release all communications and briefings regarding the decision not to issue the HAN, which he originally asked for in January.

He also demanded to see the completely redacted 17 pages of apparent COVID-19 talking points that the Biden White House sent out to the America's top public health officials.

“What is clear from these excessive redactions, however, is a concerted effort to obscure Congress’ and the public’s understanding of your agencies’ detection of and response to COVID-19 vaccine adverse events such as myocarditis and pericarditis,” Johnson concluded. “Ultimately, despite your agencies’ awareness of the risks associated with the COVID-19 vaccines, the main talking point from these and other public health officials was uniform and entirely deceptive: the vaccines are safe and effective.”

Johnson, ranking member of the committee for a short time longer until the majority flips from Democrats to Republicans with seating of the 119th Congress, has sent more than 60 public letters to federal agencies regarding the origins and treatment of the COVID-19 virus.

His demands come as the GOP-led House Energy and Commerce Committee released a report showing the Biden administration spent $900 million promoting faulty health messaging around the COVID-19 virus and vaccines.