SEOUL/BEIJING/TOKYO - When South Korea hosts the first trilateral summit with China and Japan in four years beginning on Sunday, the three neighbours may struggle to go beyond surface-level diplomacy after years of deteriorating ties, diplomats and officials said.

Still, even handshakes would help maintain at least some high-level diplomacy after a pause since the last such summit in 2019, according to officials and members of the diplomatic community in Seoul and Tokyo.

President Yoon Suk Yeol will have bilateral talks with Chinese Premier Li Qiang and Japanese Prime Minister Fumio Kishida on Sunday, then hold their three-way gathering on Monday.

The absence of Chinese President Xi Jinping effectively keeps military, foreign affairs, and security issues off the agenda, said Kang Jun-young, director of Center for International Area Studies at Hankuk University of Foreign Studies in Seoul.

On the agenda are economics and trade, climate change, cultural exchanges, health and aging populations, science, and disaster response, according to Yoon's office.

But the gathering will be constrained by the global concerns that have increasingly divided U.S.-allied South Korea and Japan from China.

“I’ve been doing this for a long time – there are lots of bilateral issues between the countries, but there isn’t anything we can do as a group," said one diplomat based in the region. "We compete on a lot of things and obviously South Korea and Japan are U.S. allies so that makes things extra challenging.”

The diplomat said the summit would be mostly “cultural” and borderline meaningless, but that China would likely seek something about supply chain stability in the joint statement.

One South Korean official said just having the three countries meet again after a long time is meaningful by itself.

Even without major breakthroughs on the toughest issues, the summit could make progress in areas of practical cooperation like people-to-people exchanges and consular matters, he said.

"That’s important as it could have a direct impact on people’s lives," the official said.

Two Japanese foreign ministry officials also said they did not expect any big announcements from the meeting and that it was important for optics that the summit resumed after a long gap.

A Japanese government official said on Friday that the countries had yet to decide whether they would release a joint statement, in part because simply setting up the meeting had faced scheduling difficulties.

The officials spoke on condition of anonymity to discuss diplomatic proceedings.

China's foreign ministry spokesman Wang Wenbin told a briefing on Thursday that Beijing hopes the talks "will inject new impetus into the trilateral cooperation and provide better ways towards mutual benefit for the three countries."

RESTRICTED ACCESS

Observers say to make any progress on even baseline issues, Beijing will need to address South Korean and Japanese concerns about the increasing difficulty of operating or doing business in China.

South Korean diplomats routinely complain about the minimal level of access they get to senior officials in Beijing. They have also watched apprehensively in recent months as China's partners, Russia and North Korea, have become increasingly close.

Japanese sources based in Beijing say they are most concerned about visas, safety of staff, and IP protection, as well as the future of auto exports to China in coming years.

Another bone of contention is the opacity of China's judicial system and the arbitrary detention of foreign business people, said Akira Amari, a senior Japanese ruling party lawmaker and former trade minister.

"The CCP (Chinese Communist Party) and the government need to establish clear standards for foreign investments and foreign personnel, because without them, they can arbitrarily detain or imprison people on a whim. If they continue on that course, investments will stall, and they will close themselves off from the world," he said.

Amari, who advises a parliamentary group promoting relations between Japan and China, said Tokyo needed to have frank discussions with Beijing so "that proper relations can continue and unnecessary tensions don't increase".

U.S. INFLUENCE

The neighbours had agreed to hold a summit every year starting in 2008 but the initiative has been disrupted by diplomatic spats and the COVID-19 pandemic.

A sore point for Beijing is the closer cooperation between South Korea, Japan, and the United States in response to China's muscle-flexing in the South China Sea and Taiwan.

Yoon has worked to improve ties with Japan, which occupied the Korean peninsula and parts of China, among other areas in Asia, before World War Two.

He has also more openly sided with Washington on issues ranging from trade to democratically governed Taiwan, which China claims as its own.

The summit is taking place against the backdrop of massive Chinese war games around Taiwan in what Beijing has called punishment for the island's new president, Lai Ching-te.

The Japanese official said that Taiwan may be addressed, and that tone of such discussions may depend on what kind of military activities take place around the island ahead of the summit.

China condemned Yoon last year after he told Reuters in an exclusive interview that increased tensions around Taiwan were due to attempts to change the status quo by force, and he opposed such a change.

Relations between South Korea and China have been frayed since the installation in South Korea of the U.S. Terminal High Altitude Area Defence (THAAD) system in 2017, under Yoon's predecessor, to better counter North Korea's evolving missile threats.

(Reporting by Hyonhee Shin in Seoul, Antoni Slodkowski in Beijing, and Kaori Kaneko in Tokyo; Additional reporting by Josh Smith in Seoul, and Sakura Murakami, John Geddie and Tim Kelly in Tokyo; Writing by Josh Smith; Editing by Stephen Coates and Kim Coghill)