SEOUL (Reuters) - Two of North Korean leader Kim Jong Un’s closest aides - a former military intelligence chief and the country’s foreign minister - are being talked of as the most likely candidates to negotiate with U.S. Secretary of State Mike Pompeo on denuclearization.

FILE PHOTO: Singapore Foreign Minister Vivian Balakrishnan meets North Korean Foreign Minister Ri Yong Ho at Singapore's Ministry of Foreign Affairs in this handout photo supplied by the Ministy of Foreign Affairs, June 11, 2018. Ministry of Foreign Affairs/Handout via REUTERS/File Photo

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Whether Kim will plump for his hardline former spy chief Kim Yong Chol or genteel career diplomat, Foreign Minister Ri Yong Ho, could provide a clue on what approach Pyongyang will take at the talks, political analysts and experts on North Korea said.

Kim Jong Un vowed in a joint statement at Tuesday’s historic summit in Singapore with U.S. President Donald Trump to work for denuclearization, and Trump promised security guarantees for North Korea in exchange.

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They offered few details, and agreed to hold talks “at the earliest possible date” to implement the outcomes of the summit with Pompeo leading the U.S. side. But the statement did not specify his North Korean counterpart by name, saying it would be a “relevant, high-level” official.

That would restrict the possible candidates to a handful of men trusted by Kim within North Korea’s highly opaque leadership circle.

Both Kim Yong Chol and Ri accompanied Kim Jong Un to Singapore for the summit and were seated with him at the table during talks that included the two delegations.

Kim Yong Chol’s center-stage presence before and during the recent thaw between the two Koreas and Pyongyang and Washington indicate he is one of the most powerful, closest aides of the young leader.

But he has chiefly dealt with inter-Korean relations, rather than nuclear issues, which have mostly been handled by the foreign ministry.

“The absence of the North Korean name in the joint statement, despite the role that Kim Yong Chol has played so far, could mean Kim Jong Un is agonizing over whether he should now charge diplomats to do the job,” said Shin Beom-chul, a senior fellow at the Asan Institute for Policy Studies in Seoul.

SPY CHIEF OR DIPLOMAT?

Kim Yong Chol, 72, is a four-star general, vice chairman of the Central Committee of the ruling Workers’ Party, and director of the United Front Department, which is charge of inter-Korean ties.

He visited Trump in Washington in late May, and has met Pompeo four times, twice in Pyongyang, once in New York and then during the summit.

“Kim should be the most likely partner of Pompeo, having worked with him before and knowing well about what Kim Jong Un wants,” said Cheong Seong-chang, a North Korea leadership expert at the Sejong Institute south of Seoul.

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Kim Yong Chol has spent nearly 30 years in the intelligence community, including a stint as chief of the Reconnaissance General Bureau, North Korea’s main spy agency.

The United States and South Korea blacklisted him for supporting the North’s weapons programs in 2010 and 2016, respectively.

Seoul accused him of masterminding deadly attacks on a South Korean navy ship and an island in 2010. He was also linked by U.S. intelligence to a devastating cyber attack on Sony Pictures in 2014.

North Korea denied any involvement in any of the incidents.

A hawkish army commander, he has steered a series of inter-Korean military talks since the late 1980s.

He was “best at pressing and humiliating” his opponents during negotiations, according to a retired South Korean diplomat who met him. In 2014, he “stormed out of the room” during military talks when the South demanded an apology for the 2010 attacks, said former South Korean military officials involved in the meeting.

“He’s known as a hard-liner, as much as Pompeo in Washington, but both people are realists who can make a compromise if necessary,” Cheong said.

WESTERNIZED, PROFESSIONAL

In contrast, Ri Yong Ho is seen as a genteel, soft-spoken career diplomat who is polite and humorous but can also be tough with sharp debating skills.

He called Trump “President Evil” at the U.N. General Assembly last year, but such rhetoric is usually out of character for him, according to former counterparts and colleagues.

A fluent English speaker, the 62-year-old Ri has held a number of high-level posts dealing with the West, including as envoy to the now defunct six-party talks aimed at dismantling Pyongyang’s nuclear programs.

Following a rare party congress in 2016, Ri was appointed foreign minister and promoted to the party’s politburo, the opaque, all-powerful party organ where top state affairs are decided. It was the first time in two decades that a career diplomat was named to the politburo, Cheong said.

“It would be reasonable for the foreign ministry that has professional expertise and experiences to take over nuclear talks,” said Chun Yung-woo, a former South Korean representative to the six-party talks.

“The summit’s joint statement simply heralded the start of working-level negotiations, where all key, complex issues will be discussed, including the timeline of the North’s dismantlement, its verification and corresponding U.S. action.”

Another potential negotiator is Ri Su Yong, a former foreign minister who is currently responsible for international affairs at the party.

While serving as ambassador to Switzerland, the 78-year-old Ri oversaw the young Kim’s European education, which helped him earn the trust of the leader, but he is seen as a long shot compared to the other two.

A senior South Korean official, who spoke on condition of anonymity, said the candidate chosen could be a factor in the approach to the negotiations, but not in North Korea’s position.

“Whoever sits at the negotiating table, any solid, specific decision on denuclearization would be made by Kim Jong Un himself,” he said.