Uganda's AIDS commission has called an HIV bill passed by parliament "nonsensical", and urged the country's president not to sign it into law.
Uganda's parliament passed new legislation criminalising the deliberate transmission of HIV, the virus that can lead to AIDS, in May.
MPs argue that the move is necessary to halt a rise in infections.
However, rights groups argue that the new law, if signed by President Yoweri Museveni, will only further stigmatise those living with HIV and dissuade people from getting tested.
Yesterday, the government's own AIDS body said the law would hamper efforts to stem the spread of the virus.
Uganda was once heralded as a success story in the fight against HIV, with Mr Museveni among the first African leaders to speak openly about AIDS.
The government mounted a highly successful public awareness campaign in the late 1980s and 1990s, causing infection rates to drop from double to single digits.
But according to the most recent statistics, the national prevalence rate rose to 7.3% in 2011, from 6.4% in 2004-05, with health officials blaming increased complacency.