BEIJING (BLOOMBERG) - The United Nations' top human rights official will on Saturday (May 28) debrief on her controversial trip to China, including its remote Xinjiang region where the US accuses Beijing of committing genocide.

Ms Michelle Bachelet will hold a press conference to mark the end of her landmark trip that began last Monday, and which she said at its outset was not an "investigation." Bachelet's visit has been criticised for failing to secure guarantees of unfettered access to Xinjiang, where a 2019 United Nations assessment said an estimated 1 million people have been detained.

US Ambassador Nicholas Burns voiced to Ms Bachelet "profound concerns" about Beijing's attempts to manipulate her trip, according to people on a Monday call who asked for anonymity as they weren't authorised to speak.

Beijing claims the facilities in Xinjiang are vocational training centres to counter religious extremism and bring prosperity to the region and vehemently denies accusations of genocide, a major source of tension between the world's two largest economies.

Earlier in the week, President Xi Jinping held a call with Ms Bachelet, an unusual move for a leader who usually speaks with other heads of state that underscored the importance China places on her visit.

Chinese state media later said Ms Bachelet praised China's track record on human rights on the call - something her office later appeared to deny in an emailed "clarification" of her "actual" remarks.

She also met Chinese Foreign Minster Wang Yi, who was pictured holding a copy of book by Mr Xi on human rights, and addressed students at Guangzhou University, in southern China, on a broad range of topics including human rights and sustainable development.

Philip Alston, a law professor at New York University School of Law, said on a Friday webinar that despite the criticism Ms Bachelet's trip was "extremely important" because it put a spotlight on Xinjiang and demanded accountability from China.

The former special rapporteur to the UN Human Rights Council said claims Ms Bachelet had walked into a trap were "silly".

"She's highly experienced, she's very sophisticated," he said of the 70-year-old former two-term president of Chile. "She's totally aware of all of the different political dimensions of what she's undertaking."