BEIJING ? China's Internet watchdog issued a new set of rules on domain name registration this week in a bid to curb pornography and illegal content.

According to Liu Jie, an official at the Ministry of Industry and Information Technology, the regulations posted on its website Sunday beef up existing rules on domain name registration.

The measures will cut off Internet services to those websites that have not registered with the ministry, Liu said.

They also aim to improve a "blacklist system" to prevent banned domain name owners from reapplying for a new domain name, he added.

It was not clear if the new rules apply to overseas websites but many such sites are already blocked by China's Internet authorities, including YouTube, Facebook, Twitter and a host of media and news websites and blogs.

China maintains strict censorship of the Internet, an effort that has become known as the "Great Firewall of China".

In recent weeks, Chinese regulators closed down hundreds of video sharing websites while ordering sites to delete all links to downloaded films or TV series, the China Business News reported earlier this month.

As of November 30, authorities had shut down 414 video and audio websites this year for operating without a license or for containing pornography, copy-violating content or other "harmful" information, the paper said.

Authorities this month offered rewards of up to 10,000 yuan (1,465 dollars) to Internet users who report websites that feature pornography, a campaign that appears to have encouraged Internet users to look for porn online.

China has launched several Internet crackdowns on pornography, con artists and political activists in the past.

Earlier this year Beijing threatened to sanction major websites, including search engine giants Google and Baidu, alleging that pornography and other material that could corrupt young people was turning up in search results.