The logo of Aliyun, Alibaba Group Holding Ltd's cloud computing arm, in Beijing. [Photo / IC]

China's copyright regulator has strengthened law enforcement to combat piracy in cloud storage services.

Despite a previous crackdown, the services have long provided Internet users with a covert channel to download movies and TV series.

Cloud service providers have been ordered to prevent users from uploading, storing or sharing files that may infringe copyright, under a regulation issued by the National Copyright Administration.

The regulation states that providers must punish copyright offenders by putting them on a blacklist or by suspending or terminating their services.

Providers should also inform copyright holders how to lodge complaints and commit to handling these promptly.

Cloud storage, which has become increasingly popular among Internet users, allows them to store files and access them from anywhere, share them with friends, and synchronize content with their mobiles and tablets.

Yu Guofu, a Beijing lawyer specializing in the protection of online intellectual property rights, said the majority of cloud storage users are white-collar workers.

"However, some users upload popular works, including drama series and music, for profit, severely infringing copyright. ... Some users also share illegal work, such as pornography. The goal is to eliminate these illegal users," said Yu, who took part in discussions on the new regulation.

Ci Ke, an official with the National Copyright Administration, said the new regulation aims to encourage all parties to explore new commercial models that meet the needs of Internet users without compromising copyright laws.

Qihoo 360, a leading cloud storage service provider, applauded the government's efforts to enhance copyright protection in cyberspace.

Since launching its cloud storage service in 2012, the company has set up a copyright protection system to meet the requirements of regulators, the head of cloud services at the firm, who preferred to remain anonymous, said.

Apple China declined to comment on the new regulation.

Xinhua contributed to this story.