The Bahati Bill, as it is called in Uganda, seeks to impose the death penalty for 'aggravated homosexuality' [EPA]

The European Parliament has urged Uganda to decriminalise homosexuality and protect gays and lesbians after a prominent gay rights activist was murdered last month.

The 27-nation assembly adopted a resolution on Thursday calling on Ugandan authorities to conduct an in-depth investigation into the murder of David Kato and probe individuals who publicly called for his killing.

It urged Uganda to ensure gays and lesbians "are adequately protected against violence, and to take prompt action against all threats or hate speech likely to incite violence, discrimination or hostility towards them".

The call came on the same day that a leaked US embassy cable on WikiLeaks revealed that Kato was mocked at a UN-backed debate on Uganda's anti-homosexuality bill where a member of the Uganda Human Rights Commission "openly joked and snickered" with the supporters of the bill.

According to the cable, the debate in December 2009 was organised with funding from the UN and sought to discuss a controversial bill seeking to impose the death penalty for "aggravated homosexuality" for consenting adults who have gay sex.

A US diplomat quoted in the cable said Kato delivered a well-written speech against the bill introduced by a born-again MP, David Bahati, but his words were almost inaudible due to "his evident nervousness".

Homophobia in Uganda runs deep and ministers and pastors often rail against gays and lesbians, accusing  them of importing and adopting "rotten"  Western culture.

Kato's murder on January 26 triggered a wave of condemnation from rights groups who criticised Uganda for ignoring the plight of gay people in the country and urged authorities to investigate the murder.

Although the Ugandan police have since arrested a suspect in connection with Kato's murder, they insist his death was a not a consequence of his gay activism.

The suspect is a male prostitute who confessed to murdering Kato after he reneged on an agreement to pay for sex, police say.

Last year, Kato was named and pictured by an anti-gay tabloid called Rolling Stone in a story that carried the headline "Hang Them" in reference to gay rights campaigners.

The people who appeared in the tabloid are "now in genuine danger of being persecuted, are in most cases now homeless, unemployed and forced to avoid public places, and must hide from public view," the parliament resolution said.