Osama bin Laden’s Al-Qaeda network has taken up the cause of China’s Muslim Uighur minority with a pledge to attack Chinese workers in northwestern Africa in retaliation for mistreatment by Beijing of its largest Muslim minority.

Al-Qaeda's Algerian-based offshoot, al-Qaeda in the Islamic Maghreb (AQIM), has issued the call for vengeance, according to the South China Morning Post, which quoted an intelligence report from the London-based risk analysis firm Stirling Assynt.

It would be the first time that bin Laden’s organisation has threatened China or its interests — underlying the risks Beijing faces as it expands its economic investments overseas.

The assessment by Sterling Assynt warned that the threat should be taken seriously and said: “Although AQIM appear to be the first arm of al-Qaeda to officially state they will target Chinese interests, others are likely to follow."

The unrest in China’s westernmost Xinjiang region last week in which 184 people died — most of them Han Chinese killed by Uighurs — has elicited sympathy in much of the Muslim world for the minority Uighurs who face tight controls on their religious practices and discrimination in the workplace.