Zhou Yongkang, China's ex-security chief who is under investigation on allegations of seriously violating Party political, organizational and confidentiality discipline, once formed a clique with Bo Xilai, the former Party chief of Chongqing who was sentenced to life imprisonment for corruption, according to a report by Phoenix Weekly, a magazine run by Hong Kong broadcaster Phoenix Television.

An article in the latest edition of the magazine said Zhou and Bo, both former members of the Political Bureau of the Central Committee of the Communist Party of China, the top Chinese leadership body, had an off-the-record talk in Chongqing.

During the talk, the article said, Zhou and Bo agreed that a theory proposed by Chairman Mao Zedong that the contradiction between the proletariat and the bourgeoisie is the principal contradiction in Chinese society is correct and that the policy of reform and opening-up, proposed by the former top leader Deng Xiaoping, should be adjusted.