The International Criminal Court (ICC) on Monday rejected calls to investigate China for alleged genocide and crimes against the Uygurs in the country's remote Xinjiang region, the chief prosecutor office said in a report on Monday.

Prosecutor Fatou Bensouda's office said it was unable to act because the alleged acts happened on the territory of China, which is not a signatory to The Hague-based ICC.

"This precondition for the exercise of the court's territorial jurisdiction did not appear to be met with respect to the majority of the crimes alleged," the ICC report said.

There was also "no basis to proceed at this time" on separate claims of forced deportations of the Uygurs back to China from Tajikistan and Cambodia, the report said.