As tensions simmer ahead of an international tribunal’s ruling on Beijing’s claims over the South China Sea, a veteran Chinese foreign policy maker is sending a stern warning about putting the verdict into action.

Dai Bingguo, a retired official who spent nearly two decades at the center of China’s foreign-policy making, urged the U.S. in a speech Tuesday to scale back its “heavy-handed intervention” in the disputed waters and accused Washington of sowing discord and provoking Beijing.

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