Pakistan, Feb. 5 -- UN Secretary-General Antonio Guterres on Wednesday warned that the expiration of the New Strategic Arms Reduction Treaty (New START) between the United States (US) and Russia marks a "grave moment for international peace and security," ending decades of legally binding limits on the world's two largest nuclear arsenals.

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"The expiration of the New START Treaty, as of midnight today, marks a grave moment for international peace and security," Guterres said, emphasizing that "for the first time in more than half a century, we face a world without any binding limits on the strategic nuclear arsenals of the Russian Federation and the United States, the two ...