A prominent LGBT rights activist in Uganda, where sexual minorities say they have faced a wave of abuse since a harsh anti-gay law was enacted last year, was stabbed on Wednesday and is in a critical condition, his organisation said.

Steven Kabuye was "stabbed to near death by unknown assailants a few meters from our home as he was heading for work this morning", Coloured Voices Media Foundation-Truth to LGBTQ Uganda, said on the social media platform X.

Coloured Voices shared a video that showed Kabuye writhing in pain with an apparent gushing wound on his wrist and a knife protruding from his stomach.

A police spokesperson said he was unaware of the attack and would look into it.

Frank Mugisha, Uganda's most prominent LGBT activist, said he believed it was motivated by homophobia fuelled by the law, which is one of the strictest in the world.

"The deep hate for sexual minorities that the law unleashed created an atmosphere in which such attacks are happening," Mugisha said.

The law prescribes the death penalty for certain same-sex acts. At least seven people have been arrested under it, and rights activists say it has also led to a surge of abuse by private individuals against LGBT people, including rapes, torture and beatings.

Uganda's government has denied this is happening and said the law is meant to criminalise same-sex activity and its promotion, not penalise LGBT Ugandans.

A Ugandan court heard a petition last month that says the law violates constitutionally protected rights. It has not yet issued its ruling.