Pakistan, Feb. 6 -- The United States accused China of secretly testing nuclear weapons in 2020, calling for a broader arms treaty including Beijing. The announcement came at a global disarmament conference in Geneva, a day after the New START treaty between the U.S. and Russia expired. Washington urged the need for a new agreement as China rapidly expands its nuclear arsenal.

U.S. Under Secretary of State Thomas DiNanno claimed China concealed "yield-producing tests" using methods to evade seismic monitoring. He warned that China could have more than 1,000 nuclear warheads by 2030. DiNanno stressed that a bilateral treaty only with Russia is no longer sufficient in the modern nuclear landscape.

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