Beijing's propaganda machine has outwitted the UN human rights chief on her visit to China, campaigners say, leaving the envoy accused of playing a role in whitewashing abuses against minorities in Xinjiang.

Michelle Bachelet's long-planned trip this week has taken her to the far-western region where Beijing is accused of imprisoning over one million Uyghurs and other Muslim minorities, forcibly sterlising women and running labour camps that fuel global supply chains.

The United States and multiple western lawmakers have labelled the actions a "genocide", allegations vehemently denied by China which says it has only conducted necessary security operations to squash extremism and beef up development.

Chinese state media has run gleeful readouts of meetings between Michelle Bachelet and Xi Jinping
Chinese state media has run gleeful readouts of meetings between Michelle Bachelet and Xi Jinping OHCHR via AFP / Handout

Bachelet has come under fire from rights groups and Uyghurs overseas, who say she has been suckered into a slickly choreographed Communist Party tour including a conversation with President Xi Jinping later portrayed in state media as a mutual endorsement of China's high ideals on rights.

The UN envoy is due to give press briefing late Saturday as her trip ends.

She is expected to be quizzed on her access to Uyghur residents and detention facilities in Xinjiang, giving her a final chance while inside China to address the allegations of abuse.

It is "as clear as day" that China has so far used the visit "to promote its own narrative and defend its poor human rights record", said Alkan Akad, a China researcher at Amnesty.

Graphic on selected reports on the human rights situation in China's Xinjiang region.
Graphic on selected reports on the human rights situation in China's Xinjiang region. AFP / John SAEKI

The goal is "to show the world that it can bend a top UN human rights official -- and thus the very concept of human rights -- to its will," said Maya Wang, senior China researcher at Human Rights Watch.

London-based Uyghur activist Rahima Mahmut slammed the visit as "window dressing".

"This is not the neutral, independent, unfettered investigation that we were promised," she told AFP.

Beijing is accused of imprisoning over one million Uyghurs and other Muslim minorities in Xinjiang
Beijing is accused of imprisoning over one million Uyghurs and other Muslim minorities in Xinjiang THE VICTIMS OF COMMUNISM MEMORIAL FOUNDATION via AFP / Handout

Instead, Beijing was seeking "a free pass to continue carrying out repression, surveillance, torture and genocide against communities like mine", she added.

Bachelet has been in Xinjiang since Tuesday with her office saying she planned to visit the regional capital Urumqi and the ancient Silk Road city of Kashgar.

Many Uyghurs overseas say relatives back in China have disappeared into custody
Many Uyghurs overseas say relatives back in China have disappeared into custody AFP / Ozan KOSE

Yet the hard details of what she saw and who she met have been largely withheld on a trip carried out in a "closed loop" by order of Beijing, ostensibly due to Covid risks.

China has filled the information vacuum, with state media running gleeful readouts of meetings between her and Xi as well as foreign minster Wang Yi.

They reported that Bachelet said she "admired China's efforts and achievements in ... protecting human rights" during the virtual call with Xi.

A spokesperson for Bachelet did not confirm whether the reports were accurate when contacted by AFP, instead saying the UN would not publish readouts of bilateral meetings.

A later, hurried "clarification" by the UN stopped short of denying that she had praised China's rights record. But neither side mentioned Xinjiang in their readouts.

Norway-based Uyghur activist Abduweli Ayup said he was "disappointed" that Bachelet had appeared to allow Beijing to "misinterpret" her words.

"They have already used (her) for propaganda," he told AFP.

While it is unclear what she was able to see in Xinjiang, Bachelet was presented with a book of Xi's quotations on human rights -- images that were circulated widely across Chinese media.

A steady drip-feed of state media articles timed with her visit have also lauded Xinjiang's economic development and rising incomes.

China rejects all criticism of its policies in Xinjiang and frequently slams those it deems to have waded into its internal affairs.

Beijing has denied that Bachelet's trip is an investigation, saying it is a chance to "clarify misinformation".

It is the first trip to China by the UN's top rights envoy in 17 years and comes after painstaking negotiations over the parameters of her visit, which the UN says is neither a fact-finding mission nor a probe.

The notion that Beijing would not use the visit to "put forth its own narrative" on human rights is "for the birds", said Steve Tsang, director of the SOAS China Institute.

"She must have the political courage and integrity to speak out when her words and her visit are being distorted," he said. "If she is not prepared and able to do so, she should not visit."