The South Korean politician expected to become its next president, Moon Jae-in, called on China on Tuesday to stop economic retaliation against South Korean firms over the deployment of a US missile-defence system.
Moon, speaking in a debate with other presidential contenders, said South Korea must stand up to China and protest against any unjust moves by it, but also make diplomatic efforts to resolve the issue.
China has protested against South Korea's agreement with the United States to deploy the Terminal High Altitude Area Defence system in the South against North Korea's missile threat.
China see the system's powerful radar as a threat to its security.
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