The Trump administration's decision to pause U.S. foreign aid has "substantially disrupted" supply of HIV treatments in eight countries, which could soon run out of these life-saving medicines, the World Health Organization said on Monday.

The global health agency said that Haiti, Kenya, Lesotho, South Sudan, Burkina Faso, Mali, Nigeria and Ukraine could exhaust their supply of HIV treatments in the coming months.

"The disruptions to HIV programs could undo 20 years of progress," WHO Director-General Tedros Adhanom Ghebreyesus said at a press conference.

He added that this could lead to over 10 million additional HIV cases and three million HIV-related deaths.

Efforts to tackle HIV, polio, malaria and tuberculosis have been impacted by the U.S. foreign aid pause implemented by President Donald Trump shortly after he took office in January.

The WHO-coordinated Global Measles and Rubella Laboratory Network, with over 700 sites worldwide, also faces imminent shutdown, the agency said.

This comes at a time when measles is making a comeback in the United States.

The United States has a "responsibility to ensure that if it withdraws direct funding for countries, it's done in an orderly and humane way that allows them to find alternative sources of funding," Ghebreyesus said on Monday.

Funding shortages could also force 80% of WHO-supported essential health care services in Afghanistan to close, the agency said in a separate statement.

As of March 4, 167 health facilities had shut down due to funding shortages, and without urgent intervention, over 220 more facilities could close by June.

The United States' plans to exit the WHO have also forced the UN agency, which typically receives about a fifth of its overall annual funding from the U.S., to freeze hiring and initiate budget cuts.

The WHO said on Monday that it plans to cut its funding target for emergency operations to $872 million from $1.2 billion in the 2026-2027 budget period.