A press freedom group Thursday criticised a ruling that bans Chinese journalists from quoting foreign news outlets without permission, a move that further tightens Beijing's control of the media.

The directive from China's media regulator, the General Administration of Press, Publication, Radio, Film and Television, also prohibits unauthorised use of information from "freelancers, NGOs or commercial organisations".

China's media comes under strict control by government censors, who view criticism of Beijing as a potential threat to stability that could undermine the Communist Party's grip on power.

"This directive marks a new stage in the reinforcement of censorship, which has been increasing steadily," said Reporters Without Borders.

The organisation said censorship has increased since the Communist Party held its congress last November, when new leaders were ushered in.

It also said the measures were aimed at preventing Chinese media from publishing revelations about top leaders, such as a New York Times report that revealed the family of former Premier Wen Jiabao had amassed a huge fortune.

Domestic news outlets in China boast worldwide networks, but many rely on reports from international agencies.

Information from overseas news providers dominated the international pages of the state-run Global Times and China Daily newspapers on Thursday.

All Chinese media outlets have links to state-run companies, but some newspapers and magazines have a reputation for pushing the boundaries of what the censors will allow them to get away with.