The request follows pleas by an ethnically Uighur Australian to be reunited with his wife and son.Read more
Liu Xiaoming says there is "no separation of children from their parents" in China's Xinjiang region.
The BBC's John Sudworth meets Uighur parents in Turkey who say their children are missing in China.
Some visitors to China's western province of Xinjiang are being made to install an Android smartphone app that collects text messages, contacts and other data from handsets, according to a investigation.
The Guardian, New York Times, Motherboard and two German news organisations - Süddeutsche Zeitung and NDR - have collaborated on the report.
The region is home to the Uighurs, a Muslim ethnic minority facing persecution and surveillance.
Motherboard has uploaded a copy of the software for others to inspect.
The Guardian said that the Chinese authorities had been contacted for comment but there was no reply before publication.
The BBC gets rare access to facilities in Xinjiang thought to be holding more than a million Muslims.