Both China's Xi Jinping and North Korea's Kim Jong Un have suffered from President Donald Trump's penchant for walking away from talks. Now, he'll have to worry about what they tell each other behind closed doors.
Xi's state visit to Pyongyang on Thursday - the first such visit by a Chinese president in 14 years - will showcase a renewed camaraderie between two neighbours that battled the US together in the Korean War.
The trip also sends Trump a pointed message about China's broader influence ahead of potentially pivotal trade talks between American president and Xi on the side lines of the Group of 20 summit in Osaka, Japan.
For Kim, it's another chance to demonstrate he's got options beyond a third meeting with Trump, after the second ended in collapse in February. The North Korean leader may find a more receptive audience for complaints about US after Trump rejected China's latest trade offer last month.
"Both leaders will likely seek to put pressure on Washington to conduct nuclear diplomacy with North Korea largely on North Korea's terms - through a phased, step-by-step approach to denuclearisation and including partial sanctions relief," said Mintaro Oba, a former US diplomat who worked on Korean Peninsula issues. "If anything, this visit will underscore the weakening regional support for the US pressure campaign."
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The summit comes at dramatic point in the strategic dance between the three leaders - with US ties with both China and North Korea on the downswing.
Until his recent breakdowns with Xi and Kim, Trump had managed to keep relations with either one or the other on the rise.
The problem for Trump is that China - as North Korea's dominant trading partner and sole security ally - is key to maintaining the economic isolation the US is relying on to force Kim back to the negotiating table. While China has repeatedly affirmed its commitment to the international sanctions regime it helped erect against North Korea, the country has shown its limits amid the trade showdown with Trump.
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On Tuesday, China joined Russia in blocking the UN Security Council committee that monitors North Korea sanctions from declaring that the country exceeded its annual import cap on refined petroleum products, the Associated Press said, citing two diplomats. The move came after the US and its allies accused North Korea of using illicit ship-to-ship transfers to bring in more oil, Bloomberg News reported, citing a US letter to the panel.
In a commentary published Wednesday in North Korea's ruling party newspaper, Xi said he wished to "open a new chapter" in ties. He told Kim, whom he repeatedly referred to as "Comrade Kim Jong Un," that China supported North Korea's "right direction for politically solving the issue on the Korean Peninsula."
Xi's visit - representing his fifth meeting with Kim - is part of series of moves to repair ties strained by Kim's weapons tests and other efforts to assert his independence after taking power in late 2011. The first meeting came in the early days of the US -China trade dispute last year, when Xi told Kim in Beijing that he had made a "strategic choice" to have a friendlier relationship.
"It is in China's interest to comply with UN sanctions without necessarily enforcing them, mainly for two reasons - so as not to put strain on DPRK-China relations, and to ensure that North Korea survives prolonged sanctions," said Rachel Minyoung Lee, a Seoul-based senior analyst with NKPro.
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Trump may have facilitated Xi's trip to North Korea by playing down Kim's recent tests of short-range ballistic missiles in an apparent violation of UN sanctions - approved with China's vote. During a trip to Japan last month, the US president referred to the missiles tested as "some small weapons," saying the operation "disturbed some of my people, and others, but not me."
South Korea's top nuclear envoy, Lee Do-hoon, expressed optimism about Xi's visit during an appearance Wednesday in Washington with US counterpart Stephen Biegun, noting that previous meetings between the Chinese and North Korean leaders were followed by contacts between Kim's regime and the US "I hope that this time again this pattern will apply," Lee said.
Biegun noted that China had long backed the elimination of nuclear weapons on the Korean Peninsula. "China's not doing this as a favour for United States of America - this is China's national interests," he said, adding "in this case, Chinese national interests and American national interests coincide."
Xi and Kim might discuss ways to convince Trump to drop his demands that North Korea first dismantle its nuclear arsenal before it can receive sanctions relief. China, like Russia, backs a process in which North Korea's disarmament steps are met by US rewards, arguing that it's the best way to build trust.
Chinese Foreign Ministry spokesman Lu Kang acknowledged during a briefing Wednesday that the country wields "significant" influence in North Korea, but encouraged "all parties" to do more to promote a resolution. Earlier this week, Lu dismissed a link between trade talks and the North Korean visit, saying: "Whether or not this meeting will be used as a marker or leverage, I can only say that people who think this may be over-interpreting."
Still, Xi's mere presence in Pyongyang - a place no top Chinese leader has visited since Hu Jintao in 2005 - may make the point. Trump has previously speculated after meetings between Xi and Kim that China was working to undermine nuclear talks out of spite for their trade disputes.
"Xi's visit will send a message that the strong relations between China and North Korea are critical to tackle the nuclear issue and to maintaining the peace on the peninsula, which the US should not ignore," said Wang Sheng, a professor of international politics at Jilin University in China.