President Yoweri Museveni signed the Anti-Homosexuality Bill into law after parliament watered it down. It is still among the harshest anti-LGBTQ laws in the world.
Homosexual acts are already illegal in Uganda but now anyone convicted faces life imprisonment.
The legislation imposes the death penalty for so-called aggravated cases, which include having gay sex with someone below the age of 18 or where someone is infected with a life-long illness including HIV.
In a joint statement, three of the world’s leading health campaign groups – the US President’s Emergency Plan for Aids Relief (Pepfar), UNAids and the Global Fund – said they were deeply concerned about the “harmful impact” of the legislation.