The United States is the "empire of hacking and theft of secrets", and the "biggest threat to global cybersecurity", Senior Colonel Wu Qian, spokesman of the Ministry of National Defense, said on Thursday.

For years, the US has conducted mass-scale cyber espionage, surveillance and attacks on foreign governments, companies and individuals, Wu said in response to a recent report that said the US National Security Agency collaborated with Denmark's Defense Intelligence Service to spy on European officials.

From WikiLeaks to the Snowden incident, from the CIA using Swiss encryption devices to spy on others to the recent Danish incident, Wu said these facts have proved that the US is regarded around the world as "the empire of hacking and theft of secrets", and is the "biggest threat to global cybersecurity".

Further, the US has spared no effort in militarizing cyberspace and developing its own cyberattack capability, he said, adding that the nation has the world's biggest cyberattack arsenal with over 2,000 tools at its disposal.

"We call for the international community to pushback against the US' cyber bullying and to urge the US to explain its spying operations, and the US should stop creating tension and animosity in global cyberspace," he said. "China will take all measures necessary to safeguard the country's cyber sovereignty, information security and social stability."