The United States must account for its surveillance activities against other countries and stop "antagonizing" cyberspace, a Chinese government agency said in a report.

The US Global Surveillance Record report by the Internet Media Research Center condemned the spying on Chinese leaders and companies.

It said China had become a main target for US spying efforts and Chinese leaders, scientific institutions and companies were the key victims.

Documents leaked by former US National Security Agency contractor Edward Snowden showed the US targeted Chinese leaders and telecoms equipment company Huawei Technologies.

China's Ministry of Commerce, Ministry of Foreign Affairs, Chinese banks and other telecoms companies were also spied on.

The report said the US had flouted international law, impinged on human rights and brought "great threats" to cyberspace.

It came after the two countries exchanged accusations over cyberattacks in the past week.

Last week, the US Department of Justice charged five Chinese military personnel with spying on US companies, an allegation denied and condemned by the Chinese government.

China said last week that imported technology products and services used in key sectors would have to undergo a security review process, a policy widely believed to affect leading US companies including Cisco Systems, Microsoft Corp and IBM.

Ni Guangnan, an academic at the China Academy of Engineering and a top computer scientist, welcomed the measures.

Ni said that countries, institutions and people that had been monitored by the NSA did not realize they were targeted until Snowden made the revelations, "which means these online attacks are always made quietly".

The report said the US intelligence agency even spied on the Chinese public by pretending to be players in computer games such as World of Warcraft and Second Life, adding that the majority of players of these online games are Chinese.

QQ, the chat software of Internet giant Tencent, one of China's largest technology companies, and Fetion, China Mobile's instant messaging service, were also being monitored by the NSA, documents disclosed by Snowden showed.

US wiretapping had been criticized and condemned across the world by countries including Germany, Brazil and Malaysia, the report said, adding that the Chinese government had taken measures to restrict it being monitored.

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