A U.S. official focusing on arms control has provided what he called new, declassified details of a Chinese underground ...

Remarks by a top administration official appeared to be aimed at dispelling skepticism of its assertions, as President Donald ...

A Trump administration official said that a remote seismic station in Kazakhstan measured an “explosion” in western China on ...

A US official has presented evidence of a secret Chinese nuclear test, raising tensions in global arms control discussions.

(Reuters) -U.S. President Donald Trump ordered the U.S. military on Thursday to immediately resume testing nuclear weapons after a gap of 33 years, minutes before beginning a meeting with Chinese ...

So long as it doesn't ratify the Comprehensive Nuclear Test Ban Treaty, the United States won't be able to seek short-notice, on-site inspections to deter and detect possible Chinese and Russian ...

The allegations were leveled by U.S. officials late last week. Arms control experts worry that norms against nuclear testing are unraveling.

Speaking before the Conference on Disarmament in Geneva, Russian ambassador Gennady Gatilov decried US President Donald Trump ...

ALBUQUERQUE, N.M. — Transported in the backseat of a blacked-out Plymouth sedan was the culmination of years of feverish work — a hefty plutonium core that would soon be used to trigger the world’s ...

President Donald Trump ordered the Department of War to resume testing nuclear weapons “on an equal basis” with Russia and China on Thursday, a practice halted by the U.S. in 1992. The announcement ...

Resuming full testing of nuclear weapons — as President Donald Trump called for last week — would be unnecessary, costly, undermine nonproliferation efforts, and empower the nation’s adversaries to ...