3 July 2014
Last updated at 06:01
Chinese President Xi Jinping has arrived in South Korea for a two-day visit set to focus on North Korea.
It is the first time a Chinese leader has visited Seoul before Pyongyang, and comes amid cooler China-North Korea ties.
China is North Korea’s biggest trading ally and the nation most able to wield influence over it.
But in recent months Beijing has appeared increasingly frustrated with its unreliable neighbour.
Last year, North Korea carried out its third nuclear test and there are reports that it could be planning a fourth.
Mr Xi and South Korean President Park Geun-hye are also expected to discuss growing economic ties, as the two nations work towards a free-trade agreement.
Wider strategic concerns are also in focus. Both China and South Korea are at odds with Japan over historical issues. But Seoul, like Tokyo, is a major US ally.
South East Asian nations that are, like Japan, involved in territorial disputes with Beijing are also moving closer to the US. So China will be keen to shore up ties with Seoul.
The Chinese president is said to enjoy a friendly relationship with Ms Park, with whom he will hold talks.
Lucy Williamson, BBC News, Seoul
Despite new warmth and strategic interest, the two leaders’ discussions today are likely to expose the old intractable differences at the heart of their political visions.
Both Mr Xi and Ms Park may agree that North Korea’s nuclear programme is undesirable but they differ on how to stop it.
South Korea would like Beijing to do more to pressure Pyongyang, but for decades China has made the strategic calculation that stability in North Korea comes first – in its eyes, avoiding implosion of the regime is more important than avoiding nuclear tests.
Instead, Beijing has encouraged all parties to return to talks without pre-conditions. Seoul and Washington say that amounts to “buying the same horse twice”. The discussions here will be watched for any small shifts in tone by Beijing, but the basic parameters of China’s strategic interest are unlikely to change.
Why is China’s leader visiting Seoul?
The is the fifth summit between the two since both took office. Ms Park visited Beijing last year.
Mr Xi’s visit comes a day after North Korea fired short-range rockets into the sea, the latest in a series of recent missile tests.
Ahead of the visit, Chinese Foreign Ministry spokesman Qin Gang said that pushing for the denuclearisation of the Korean peninsula remained Chinese policy.
Mr Xi and Ms Park would “fully exchange views” on the nuclear issue and the stalled six-party talks aimed at persuading North Korea to abandon its nuclear ambitions, he said.
But a key issue for China is to maintain stability in North Korea. It fears that regime collapse could propel a flood of refugees across its border and also lead to a unified Korea allied to the US.
So, while its media outlets have in recent months voiced growing concern over Pyongyang’s actions, Mr Xi is unlikely to speak out strongly.
A commentary in Chinese state-run news agency Xinhua on Thursday blamed “mutual distrust and hostility” between the US and North Korea for the “chronic” state of the Korean peninsula.
“China and South Korea are natural and major stakeholders in the Korean Peninsula issue,” it said.
“Against such a gloomy background, it is highly advisable and imperative that Seoul work hand in hand with Beijing to enhance coordination in regional affairs,” it added.