China will step up its security following allegations that the U.S. National Security Agency (NSA) collected data on millions of phone calls in Europe and snooped on leaders of major U.S. allies, the government said on Wednesday.
"Like many other countries, we have been paying close attention to these reports," Chinese Foreign Ministry spokeswoman Hua Chunying told a daily news briefing.
"China is concerned about the continued revelations of eavesdropping and surveillance and is paying attention to how the situation develops," she added.
"We will take the necessary steps to resolutely maintain the security of our own information," Hua said, without elaborating.
The head of the NSA defended his beleaguered organisation on Tuesday, saying it acts within the law to stop militant attacks and calling reports that the NSA collected data on millions of telephone calls in Europe false.
The White House has moved to limit some NSA programmes, including one that monitored the cellphone of German Chancellor Angela Merkel.
Hua would not comment on whether China also carried out large-scale monitoring of overseas telephone calls, but the country's security services are widely believed to run a sophisticated tapping operation, at least domestically.
Foreign diplomats say that visiting officials frequently have to leave their mobile telephones and laptop computers or tablets at home when they travel to China, such are the concerns about Chinese surveillance and hacking.
The Chinese government is often accused, especially by the United States, of hacking into computer networks overseas, targeting both companies and government departments.
China consistently denies the accusations, saying it is one of the world's biggest victims of hacking.
Last week, China's main state broadcaster said one of its Twitter accounts had been hacked.