BEIJING—China sees a war of words between the U.S. and North Korea as frustrating its efforts to reduce tensions on the Korean Peninsula, leaving it with few palatable options.

The threats of military action traded by U.S. President Donald Trump and North Korean state media this week drew appeals for restraint from China’s Foreign Ministry. Government news outlets warned that such rhetoric would “make things worse” and urged Washington and Pyongyang to “return to reason.”

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