BUSAN, South Korea—The two Koreas held their highest-level talks in years Saturday as a surprise visit by top North Korean officials to South Korea for a sporting event allowed the governments to break a diplomatic deadlock.

The North Korean delegation, led by Hwang Pyong So, considered by many outside observers to be No. 2 in the isolated nation’s hierarchy, met with South Korean Unification Minister Ryoo Kil-jae, National Security Office head Kim Kwan-jin and other senior officials for lunch.

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