China gave its backing on Tuesday to a Congolese provincial government's order last month banning six small Chinese-owned mining companies operating illegally.

The move comes as Democratic Republic of Congo's President Felix Tshisekedi increases scrutiny of Chinese mining activities, reviewing a $6 billion "infrastructure-for-minerals" deal with Chinese investors and reassessing China Molybdenum's Tenke Fungurume mine. 

The governor of Congo's eastern South Kivu province, Theo Kasi, suspended the operations of the six small Chinese companies on Aug 20, ordering all local and foreign staff to leave the sites.

Kasi said the suspension came after the companies missed a deadline to register their activities with the authorities.

Kasi identified the companies as BM Global Business, Congo Blueant Minerals, Orientale Ressource Congo, Yellow Water Ressources, New Continent Mineral, and Groupe Cristal, ordering all local and foreign staff to leave the sites. Reuters was unable to reach the companies for comment.

The director-general of the Chinese Foreign Ministry's Department of African Affairs, Wu Peng, tweeted that the authorities of China's Zhejiang and Jiangsu provinces had ordered the six companies to halt business and leave South Kivu "as soon as possible".

"We support the DRC in cracking down on illegal economic activities in accordance with the law," Wu tweeted. The companies would be punished and sanctioned by the Chinese government, he added. He did not identify the companies nor describe in what way their activities were illegal.

"We'll never allow Chinese companies in #Africa to violate local laws and regulations," Wu wrote.

(Reporting by Helen Reid Editing by Bate Felix and Peter Graff) ((Helen.Reid@thomsonreuters.com; +27 66 156 5214;))