Top-level officials from both North Korea and China attended the summit, including Kim's sister Kim Yo Jong and Wang Huning, a member of China's powerful seven-man Politburo Standing Committee, according to Chinese state media.
China has been North Korea's only ally in the region though their relations took a nosedive of late over Pyongyang's reckless nuclear ambitions and also China's enforcing of the United Nation's sanctions imposed on the latter to curb its tests.
China has been keen to show it has an indispensable role in seeking a lasting solution to tension over North Korea's pursuit of nuclear weapons, concerned that its interests may be ignored, especially as North Korea and the United States establish contacts.
Since then, Kim made a highly-publicised visit to South Korea and held a summit meeting with South Korean Prime Minister Moon Jae-in.
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"China's top economic adviser, the vice premier, will be coming here next week to continue the discussions with the president's economic team".
His trip was kept secret until he returned to North Korea.
Reports said the two leaders were expected to meet in Singapore.
In an unprecedented meeting at the demilitarized zone separating the two countries, Kim became the first North Korean leader to step into South Korean territory since 1953. The three Korean-Americans Kim Dong Chul, Kim Hak Song and Tony Kim are all accused by the North of anti-state activities.
The escalation began as an effort by Trump to reverse the trend of rising trade deficits the U.S. has with China, which hit a record US$375 billion in 2017 and has continued rising this year.
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Hong Kong's South China Morning Post newspaper cited two unidentified sources as saying that Xi had flown to Dalian on the coast east of Beijing to preside over the official launch of sea trials for China's first entirely self-built aircraft carrier.
The US has said North Korea must commit immediately to getting rid of nuclear weapons.
Kim held his first summit with Xi in March in Beijing, marking the first meeting since Kim took power in late 2011. A status quo, it's worth noting, that means that the decades-long USA military presence in Korea will remain for decades more to come.
At a crucial time when the regional situation is developing rapidly, Kim said he came to China again to meet Xi and inform him of the situation, hoping to strengthen strategic communication and cooperation with China, deepen DPRK-China friendship, and promote regional peace and stability.
The second meeting with Xi and the lack of details on the Trump-Kim summit - a time and location have still not been set, although Trump has said an announcement is coming soon - has raised speculation among analysts that the summit preparations may have hit a snag.
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