Both CNN and ABC News cited defense officials on condition of anonymity.
Such a recommendation could prompt Biden to issue a presidential waiver that would make the use of COVID-19 vaccines mandatory within the military before the Food and Drug Administration gives the shots full approval. COVID-19 vaccines made by Pfizer, Moderna and Johnson & Johnson are currently only approved under emergency use authorization.
Both CNN and ABC News report that Austin's recommendation to Biden could come as soon as this week, along with a Pentagon recommendation with how to proceed.
The reports come a week after Biden asked the Department of Defense to "look into how and when" to add the COVID-19 vaccine to its list of mandatory vaccines.
ABC News reports that 70% of military personnel have gotten at least one shot of a COVID-19 vaccine. According to the CDC, 58% of the U.S. population has gotten at least one shot of a COVID-19 vaccine.
The Department of Defense already requires military members to be vaccinated against some diseases upon arrival at basic training and prior to deployment, according to the Department of Health and Human Services.
Military members routinely get vaccines to prevent "tetanus, diphtheria, pertussis, hepatitis A and B, varicella or chickenpox, measles, mumps, rubella, polio, and meningococcal," and troops stationed around the world receive other vaccines depending on the area in which they are serving.