Beijing on Wednesday slammed Washington's directions to its forces for potential "coordinated nuclear confrontations involving Russia, China and North Korea," state media reported.
"The US has been constantly hyping up the so-called China nuclear threat," said Mao Ning, spokeswoman for China's Foreign Ministry.
It is "nothing but an excuse to shift the responsibility of nuclear disarmament, expand its nuclear arsenal, and seek overwhelming strategic advantage," said Mao.
Mao was responding to US President Joe Biden's reported approval of a classified document in March directing US forces to get ready for potential "coordinated nuclear confrontations involving Russia, China and North Korea."
The document, which is revised approximately every four years, is classified to such a degree that there are no electronic versions available.
Only a limited number of hard copies have been distributed to select national security officials and Pentagon leaders, according to the New York Times.
It added, however, that in recent speeches, two senior administration officials were allowed to allude to the change prior to a more comprehensive and unclassified update to Congress that is anticipated before Biden's term concludes.
The Pentagon believes China's nuclear arsenal will rival the size and diversity of US and Russian stockpiles over the next decade, the Times reported.
However, Mao said: "China's nuclear arsenal is not at the same level as the US, and China adheres to a policy of not using nuclear weapons first, maintaining its nuclear strategy of self-defense."
Beijing is "always keeping its nuclear capabilities at the lowest level necessary for national security, with no intention of engaging in any arms race with any country," she added.
