China issued a ban starting Friday on the sale of foreign publications without an import permit, in what activists said is the next step in the ruling Chinese Communist Party's quest for total thought control.



The new rules came into effect on the online shopping platform Taobao on Friday banning sellers from offering "overseas publications."



"In order to ... create a safe and secure online shopping environment and to enhance consumer confidence and satisfaction, Taobao has embargoed sales of foreign publications," the company said in a statement on its website.



The change, which also includes foreign "services" relating to publications, will enter into force on March 10, 2017, it said.



Violations of the rule leading to "serious consequences" will result in the deduction of 48 seller points, it said.



The move comes after five Hong Kong booksellers were detained in 2015 for selling "banned books" to customers across the internal immigration border in mainland China.



An employee who answered the phone at Taobao said the ban included books, movies, and games that hadn't already been given government approval.



"If it comes from overseas, then basically, it's not allowed, for the time being at least," the employee said. "Any imported publications will need an import certificate under this system, and they need to be reported to the authorities. Only then can they be sold."



Clamping down



Pan Lu, of the Hubei-based rights group Rose China, said the administration of President Xi Jinping is currently tightening control over every aspect of public discourse.



"They are clamping down on ideology and public opinion," Pan said. "They can't afford to allow a pluralistic value system to seep into China via the consumer market for foreign publications."



"The Chinese Communist Party is terrified that its own single-party ideology is bankrupt, and it is trying to shore up its grip on power by controlling what people think."



Hangzhou-based writer Zan Aizong said the new rules would make it much harder for people to get hold of foreign literature.



"This will mean that people will have to resort to selling it on the quiet, because if you are found at the border to have political books in your bag, you will be detained," Zan said.



"It's very hard to get books into the country from overseas."



He said the only option left will be to try to download e-books from outside the complex network of blocks, filters, and human censorship known as the Great Firewall.



Still detained



More than a year after he was taken away from his holiday home in Thailand and held by Chinese police, Hong Kong bookseller and Swedish national Gui Minhai remains in detention at an unknown location.



Gui, who headed the Mighty Current publishing house based around the Causeway Bay Books store in Hong Kong, is the last of five booksellers to be unaccounted for after their cross-border detentions sparked accusations that Beijing had broken its treaty obligations to the city.



He was last seen on Oct. 17, 2015 after leaving his holiday apartment in Pattaya, Thailand, according to the Free Gui Minhai website set up by his daughter Angela to campaign for his release.



In the months that followed, Causeway Bay Books store manager and British passport-holder Lee Bo, 65, went missing from his workplace in Hong Kong, and the group's general manager Lui Bo (also spelled Lui Por) and colleagues Cheung Chi-ping and Lam Wing-kei were also all detained under opaque circumstances.



The five are all permanent Hong Kong residents, and the now-shuttered bookstore operated under the laws of that city, not Chinese law.



Reported by Lee Lai for RFA's Cantonese Service, and by Xin Lin for the Mandarin Service. Translated and edited by Luisetta Mudie.



