The United States is the primary source of nuclear threat in the world, Chinese Foreign Ministry spokesperson Mao Ning said on Friday.

Mao's comment came at a regular news briefing when asked to comment on media reports that Homeland Security Advisor to US President Elizabeth Sherwood-Randall said that the United States needs to invest China in work to diminish nuclear threats.

"Calling China a 'nuclear threat' is a convenient pretext for the United States to expand its own nuclear arsenal and keep its military hegemony," Mao said.

She underscored that China has always been extremely prudent and responsible about its nuclear policy, following a defensive nuclear strategy and a policy of "no first use" of nuclear weapons, and keeping its nuclear capabilities at the minimum level required by national security.

China has strictly fulfilled its obligations on nuclear nonproliferation and followed a rational, coordinated and balanced approach to nuclear security, and is committed to the peaceful use of nuclear energy, and help the world benefit from nuclear energy as much as possible, Mao said.

Mao said China values international cooperation on the peaceful use of nuclear energy, and has made important contribution to protecting the security of nuclear facilities and reducing the risks of nuclear proliferation.

The United States, as the most powerful nuclear weapon state, is supposed to follow a responsible nuclear policy. However, the US has in recent years invested heavily to upgrade its nuclear triad, heightened the role of nuclear weapons in its national security policy and built up a network of military alliance around the globe. The United States has also built small blocs reminiscent of the Cold War by bolstering extended deterrence and conducting nuclear submarine cooperation, according to the spokesperson.

"It is the United States who is the primary source of nuclear threat in the world. The US should fully reflect on its nuclear policy, step up to its special and primary responsibilities of nuclear disarmament, and reduce the role of nuclear weapons in national security policy," Mao said.

She called on the United States to take meaningful, practical steps to reduce nuclear risks and act responsibly to maintain the strategic stability of regional and global peace and security.