BEIJING - North Korean leader Kim Jong Un has inspected a project to build a nuclear-powered submarine, state-run media reported Thursday, underscoring Pyongyang's push to strengthen its naval capabilities.

Kim criticized U.S.-South Korean plans to build nuclear-powered submarines, saying they would heighten instability on the Korean Peninsula and require a response, according to the official Korean Central News Agency, which for the first time released photos of a North Korean nuclear-powered submarine.

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