The channel, which has a reputation for breaking taboos and has been accused of obscenity and tastelessness in the past, will cross a new threshold with the scenes of cannibalism to be shown on Thursday.

The documentary, Beijing Swings, which covers the extreme practices of some modern artists in the Chinese capital, has been condemned by the country’s embassy in London and by politicians and lobby groups in Britain.

“This artist is being controversial for controversy’s sake, not for art. It is also typical of Channel 4 to try to be sensationalist,” said John Milton Whatmore, chairman of Media Watch.

Hung Liu, third secretary at the Chinese embassy, described Channel 4’s programme as “detrimental” to China. “This is a wrong image and very damaging,” he said.

Beijing Swings shows stills of Zhu Yu, the artist, eating what appears to be a stillborn infant. There is one shot of him washing the baby before he eats it and then three of him biting into the body. Zhu Yu admits he was sick afterwards.

“What will be seen is very disturbing, but we will be making sure viewers are told what to expect,” said Jess Search, the Channel 4 executive in charge of the broadcaster’s forthcoming season of programmes about China. “There will be a very strong warning.”

She justified the programme by saying China is “at a moment of change socially and culturally. We wanted a portrait of a young and modern China”.

Zhu explains his stunt by claiming: “Our subconscious tells us that eating babies is not right. But it is not prohibited. No religion forbids cannibalism. Nor can I find any law which prevents us from eating people. So I took advantage of the space between morality and the law and based my work on it.”

Zhu, who claims to be a Christian, says his religion has a major impact on his art. “Jesus is always related to blood, death and wounds and this is reflected in my art.”

Ann Widdecombe, the Tory MP and former shadow home secretary, said she was appalled that Zhu was using his religion to justify his actions. “Jesus Christ said suffer the little ones to come unto me, not that they should be eaten for public entertainment. This programme sounds hideous.”

The programme shows photographs rather than film so some critics may say Zhu could have faked eating the baby. “I’m absolutely convinced it happened,” said Waldemar Januszczak, the Sunday Times art critic who presents Beijing Swings.

“We’d heard about Zhu Yu and wanted to talk to him. The authorities in China are worried about this type of art yet it does happen.”