South Korean presidential spokesman Kim Eui-kyeom made the comments a few hours after Kim arrived in Beijing on Tuesday aboard a special train for a four-day visit.
A whirlwind of diplomacy enveloped the Korean peninsula a year ago, with Kim also meeting the South's President Moon Jae-in three times, and culminating in his high-profile Singapore summit with Trump in June.
This is Kim's fourth trip to China since his maiden visit in March past year.
Washington is pressing the North to offer up a detailed accounting of its nuclear arsenal, while Pyongyang says it has already done enough and it's time for the U.S.to ease harsh global sanctions that hold back the North Korean economy.
Rumors of another visit came late Monday night as a North Korean train passed into the Chinese city of Dandong under heavy security.
South Korea's Yonhap News Agency speculated the train could be carrying a senior North Korean official, while the Hankyoreh newspaper cited sources as saying Kim was in China for a summit.
A three-car North Korean train pulled into Beijing Railway station Tuesday morning shortly after China's Xinhua News Agency confirmed Kim would be visiting the country January 7-10.
The visit by Kim suggests that he is seeking Xi's advice or highlighting his country's alliance with China as he prepares for another meeting with Trump.
China remains North Korea's closest ally, extending a cross-border economic lifeline to the cash-strapped and heavily sanctioned state, and China has called for economic sanctions on North Korea to be eased.
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A second summit could address concerns to global security after Kim piled pressure on Trump by threatening in his annual New Year's address to take a "new path", if the USA didn't relax economic sanctions.
Tuesday also happens to be the reclusive North Korean leader's birthday.
US Commerce Secretary Wilbur Ross said on Monday on US television that "there's a very good chance that we'll get a reasonable settlement that China can live with, that we can live with and that addresses all the key issues".
After Kim traveled to China in March 2018 in his first foreign trip as North Korea's leader, Beijing and Pyongyang have deepened their ties.
Washington is demanding Pyongyang give up its nuclear arsenal before any relief from economic sanctions is granted, while the North is insisting on immediate concessions from the US.
Last week, Trump said he had recently received a "great letter" from Kim, but declined to reveal its contents. Providing the bulk of both North Korea's diplomatic support, trade and aid.
"Acting ambassador Jo Song-gil's term was ending in late November previous year and he escaped the diplomatic compound in early November", the MP said.
Kim had gone to China at Xi's invitation, according to the reports, and would stay in China from January 7 to 10. Kim is also expected to meet Moon again soon, possibly in Seoul.
Also on board the armour-plated, luxury train was Kim Yong-chol, the former spy chief who has been heading negotiations with U.S. secretary of state Mike Pompeo - negotiations that haven't got very far to date.
"Their behavior has demonstrated that as well and we appreciate that".