China's National Security Law reinforces government controls over cyberspace and covers a wide range of other areas including the economy, social stability, territorial integrity, the military, culture, finance, technology, the environment and food safety.
The law "raises many concerns due to its extraordinarily broad scope coupled with the vagueness of its terminology and definitions," Zeid Raad al-Hussein, the UN high commissioner for human rights, said in a statement issued in Geneva.
The new law is an extension of the hard line on security and repeated warnings against foreign ideological subversion issued by the government of President Xi Jinping, who in 2013 established an overarching National Security Commission to coordinate such efforts with him as chairman.
Zeid argued that national security laws need to be specific enough that people can foresee the consequences of their behavior and to safeguard against arbitrary enforcement.
He added that he welcomes the fact the new Chinese legislation specifically refers to the country's constitution and respect for human rights, but is concerned about a lack of independent oversight.