The Trump administration plans to slash annual discretionary spending at the US federal health department by around one-third, or $40 billion, The Washington Post reported Wednesday, citing a draft budget document.

A preliminary financial plan that would still require approval by Congress, the framework for the Department of Health and Human Services (HHS) comes amid massive cuts to the government under Donald Trump and his top advisor, billionaire Elon Musk.

The $40 billion of cuts proposed for 2026 would slash deeply into the $121 billion approved by Congress in 2024.

This "discretionary spending" is vastly outweighed by hundreds of billions in mandatory outlays, especially on public health insurance programs Medicare and Medicaid, which bring the total HHS budget to around $1.8 trillion.

Massive restructuring had already been announced in March for the HHS, slashing about a quarter of its staff.

Job cuts have also hit key agencies under the department's supervision, including the epidemic-fighting Centers for Disease Control and Prevention (CDC) and the Food and Drug Administration (FDA) which approves new medications.

The proposed budget "calls not only for cuts, but a major shuffling and restructuring of health and human services agencies," The Washington Post wrote.

Several branches of the National Institutes of Health (NIH) research agency would be merged.

Set to get the axe include programs on chronic disease, projects to improve rural access to health care, and early education for children from low-income families.