China is to impose security checks on information technology products and services to safeguard cybersecurity.

The State Internet Information Office said on Thursday that IT products, services and suppliers of information systems related to national security and the public interest would be reviewed.

China is the world's largest computer, telecommunications and Internet market and one of the biggest cybersecurity victims.

Foreign and domestic companies will not be allowed to sell equipment and services if they fail the review.

Details of the policy have yet to be released, but it comes at a time when China has faced increasing challenges on cybersecurity.

A Chinese cybersecurity monitoring agency said some 50,000 backdoor attacks had been launched on Chinese computers over the past two months, originating from more than 2,000 Internet protocol addresses in the United States, the biggest source of these attacks.

On Wednesday, The New York Times reported that the US National Security Agency had hacked into computers of global companies including China Telecom and Huawei Technologies Co, the world's largest telecoms network company, based in Shenzhen.

In a letter to US President Barack Obama dated May 15, John Chambers, chairman and CEO of Cisco Systems, complained about reports that the NSA intercepted US-made network devices when they were shipped to foreign customers so that it could modify the systems to collect information.

Network equipment maker Cisco Systems is a major player in China.

In October, former NSA contractor Edward Snowden revealed that the US government used its diplomatic missions in more than 80 locations, including Beijing, to collect telephone and network information.

Analysts hailed the Chinese government's decision as a necessary measure to protect national security and public interest.

"The review is necessary, especially for information systems of key industries such as finance and telecoms," said Chen Xingshu, professor of information and technology at Sichuan University.

Ni Guangnan, an academic at the China Academy of Engineering and a top computer scientist, said information systems used by government departments must be reviewed.

Wang Jun, chief engineer at the China Information Technology Security Evaluation Center, said the review would help Chinese technology and network companies to upgrade products and improve service security.

He said many countries had already enforced such reviews.

For example, the US House Permanent Select Committee on Intelligence conducted a security investigation on Chinese IT firms in 2012, which finally forced Huawei to exit the US network equipment market.

This week, the US indicted five Chinese military officers for cybertheft. But Wang said the timing of China's decision was a coincidence rather than retaliation against the US.

In February, President Xi Jinping vowed to strengthen China's Internet security and set up a central online security and informatization leading group, which he heads.