Trump and Xi Both Expected to Make Official State Visits to South Korea During APEC Summit
It makes sense that both these leaders would want to make official visits with President Lee since they will both be in Gyeongju for the APEC summit:

U.S. President Donald Trump and Chinese President Xi Jinping are both likely to pay state visits to South Korea during the Asia-Pacific Economic Cooperation (APEC) gathering later this month, diplomatic sources said Thursday.
Seoul is in talks with Washington and Beijing over the arrangements for the highly anticipated trips by the two leaders and is fine-tuning details to host both with a state visit, the sources said.
A state visit is the highest form of diplomatic visit by a foreign head of state, during which the host country extends the utmost ceremonial protocol, including an elaborate official welcome with military honors and a state banquet.
If realized, their visits would take place in Gyeongju, the host city for APEC in southeastern South Korea, rather than Seoul, possibly in a simplified manner in terms of the protocol, considering the schedules coinciding with the multilateral gathering, the sources said.
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