New Delhi, Feb. 6 -- The United States on Friday charged China with carrying out a clandestine nuclear trial in 2020 while advocating for a fresh, more inclusive arms regulation pact that would encompass Beijing and Moscow.

The allegations at an international disarmament summit underscored major frictions between Washington and Beijing during a critical juncture for nuclear weapon management, following the expiration of the accord restricting US and Russian projectile and warhead installations.

"I can reveal that the US government is aware that China has conducted nuclear explosive tests, including preparing for tests with designated yields in the hundreds of tons," US Under Secretary of State for Arms Control and International Security...