By Peter Feuilherade
China's State Administration of Radio, Film and Television (Sarft) has issued a regulation banning partnerships with foreign broadcasters, the official Chinese news agency Xinhua reported.
Foreign media firms are eager to partner Chinese companies
The regulation specifies that "all local TV and radio stations should not rent their channels to foreign companies and also should not co-operate with foreign companies in running channels".
It also bans "any co-operation with foreign companies in regular and live programmes".
International media groups have shown immense interest in China's fast-growing TV market.
The roll-out of dozens of new digital channels has boosted demand for quality content, creating opportunities for both Chinese and foreign content providers.
Last year, in an effort to open up the media market, China issued rules allowing foreign investment in joint-venture television, radio and film production companies.
This paved the way for international giants such as Viacom, Sony Pictures and Rupert Murdoch's News Corporation to negotiate deals with local partners.
As well as joint ventures, some foreign companies have sold blocks of programming, while a group including a Chinese-language channel owned by News Corporation's Hong Kong-based Star Group has been granted rights to broadcast to small areas of the mainland.
But the rules were carefully drafted to ensure that Chinese companies would not be overrun.
The regulations also preserved the ban on foreign involvement in news and current affairs-related content, reflecting the political sensitivities that have held back the reform of the media sector.
In March this year China limited most foreign companies to only one joint venture, and banned the involvement of any deemed to be "unfriendly".
The Sarft said at the time: "There is a very strong ideological component to production of broadcast television programmes... China must understand the political tendencies and background of overseas partners and prevent joint ventures or co-operation from bringing harmful foreign thinking or culture into our production sector."
"A step back"
Media analysts say the latest measure represents a step back from the more liberal rules unveiled late last year.
The South China Morning Post commented on 14 July that the move was believed to be part of a clampdown on recent attempts by regional broadcasters to use foreign capital to beef up station programming, administration and advertising.
The newspaper quoted Renmin University media professor Yu Guoming as saying that China's local media were "struggling to survive under the weight of regulations and China Central Television's monopoly on content, broadcasting channels and advertising".
"Their speedy moves to work with foreign investors were too fast and have scared media authorities," Prof Yu told the paper.