A South African celebrity has cancelled an appearance in Zimbabwe after a Christian group tried to ban him from entering the country because he is gay.

The Apostolic Christian Council of Zimbabwe wrote to the government saying it opposed Somizi Mhlongo's visit and its members felt "violated" by it.

The actor and media personality was scheduled to attend the reopening of a restaurant in Harare on Thursday.

But he later accepted an invitation to a gig in Namibia instead.

The 48-year-old appeared to be in good spirits in a video posted to Instagram on Thursday with the caption "Bye bye ZA (Zimbabwe) Hello NA (Namibia)".

Mr Mhlongo, who is best known as a judge on South Africa's version of American Idol, said that while he was disappointed at the cancellation of his visit, he would not "stop speaking on behalf of the voiceless".

"If it means you not wanting me being me, authentically me, keep it, keep your space, keep your country, I don't want to be there anyway," he said in the six-minute video.

Leaders of the Apostolic Council, a coalition of more than 600 Christian groups, said in its letter to President Mnangagwa that "Zimbabwe doesn't tolerate homosexuality".

"Spiritually we would have disturbed a lot, and physically we would have openly accepted homosexuality in Zimbabwe hence affecting our children," the group said.

The council also claimed that allowing Mr Mhlongo's visit could have a detrimental effect on the ruling Zanu-PF party in upcoming elections.

Zanu-PF's youth wing also opposed Mr Mhlongo's visit, and the party's acting deputy secretary for youth affairs said he had urged the restaurant to rethink its invitation.

Homosexuality remains illegal in Zimbabwe and its LGBT community was often violently persecuted during the rule of former President Robert Mugabe, who once said gay people were "worse than pigs and dogs".