It will be the second hotline between the two countries following one established last year between their defense chiefs, Yonhap reported.
Visiting South Korean Foreign Minister Yun Byung-se and his Chinese counterpart revealed plans for their hotline as Pyongyang's top general renewed calls for more production of "miniaturized" nuclear weapons and missiles.
Yun told a news conference in Beijing that the two sides will work closely together to convince the North not to carry out additional provocations.
China fought alongside North Korea in the 1950-53 Korean War.
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