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On July 23, 2018, Ryu was in Beijing to "strengthen its economic ties" with China. Korean Central Television reported that "Ryu was visiting Beijing, on his way to Guinea" with a stop in China. This stop "coincided with a US sanctions enforcement notice."
On May 14, 2018, Ryu arrived in China to possibly discuss "follow-up measures to what was agreed during the summit talks held last week between North Korea's Supreme leaderKim Jong Un and China's Paramount leaderXi Jinping." During this stay in China, he is reported to have stayed at the Diaoyutai State Guesthouse.