Nairobi (AFP) – President Donald Trump's decision to freeze foreign assistance has sent aid staff in Africa into "panic mode", with even HIV experimental treatment programmes stopped dead in their tracks.

Trump last week ordered a suspension of foreign assistance, while his billionaire ally Elon Musk has boasted he is putting the vast US humanitarian agency USAID "through the woodchipper".

That has included a 90-day suspension of all work by the President's Emergency Plan for AIDS Relief (PEPFAR), which alone supports more than 20 million HIV patients and 270,000 health workers, according to an analysis from the Foundation for AIDS Research (amfAR).

Among its programmes, PEPFAR currently provides anti-retroviral treatments to 679,936 pregnant women living with HIV both for their own health and to prevent transmission to their children, the analysis said.

"During a 90-day stoppage, we estimate that this would mean 135,987 babies acquiring HIV," it said.

US Secretary of State Marco Rubio, who has been named acting head of USAID, has said "life-saving treatments" would be exempt from the freeze.