The former spy chief is a trusted adviser to North Korean leader Kim Jong Un, playing a pivotal role in preparations for an historic summit between Kim and U.S. President Donald Trump.
In a sign of his importance, Trump announced Kim Yong Chol's New York trip on Twitter on Tuesday.
The White House said he would meet U.S. Secretary of State Mike Pompeo later this week, the most high-level contact between the two countries in the United States since Jo Myong Rok, a marshal, met President Bill Clinton in 2000.
Kim Yong Chol is a four-star general, vice chairman of the ruling Workers' Party's Central Committee, and director of the United Front Department, which is responsible for inter-Korean relations.
Such positions, and his omnipresence before and during inter-Korean summits in April and on Saturday, make him one of the most powerful people in North Korea, South Korean officials say.
He has played a central role in the recent thaw in relations between the North and South Korea, as well as the United States.
Sent as Kim Jong Un's envoy to the Winter Olympics in South Korea in February, Kim Yong Chol told South Korean President Moon Jae-in Pyongyang was open to talks with Washington, the first indication North Korea was changing course after months of trading threats and insults with the United States.
He and Kim Jong Un's sister, Kim Yo Jong, were the only two officials to join the North Korean leader at the two inter-Korean summits. He also coordinated Kim Jong Un's two meetings with Pompeo in Pyongyang.
SPY UNDER SANCTIONS
Kim Yong Chol was previously chief of the Reconnaissance General Bureau, a top North Korean military intelligence agency, and has spent nearly 30 years as a senior member of the intelligence community.
He was accused by South Korea 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 either incident.
Kim Yong Chol "stormed out of the room" during military talks in 2014 when the South demanded an apology for the 2010 attacks, according to South Korean officials.
"He is a tough negotiator and an expert on inter-Korean talks, but it is true that he had been a symbol of hawks rather than harmony and reconciliation until this year," said Moon Sang-gyun, a former South Korean defence official.
BODYGUARD TO KIM'S FATHER
Kim Yong Chol served in the military police in the demilitarized zone on the border of the two Koreas. He was also a bodyguard to Kim Jong Il, the former leader and late father of Kim Jong Un, according to North Korea Leadership Watch, an affiliate of the 38 North think tank.
He has been closely linked to Kim Jong Un's succession and has been seen flanking the leader on several public visits. Kim Yong Chol is known to be difficult to work with, sarcastic and not sufficiently deferential to his superiors, Leadership Watch said.
He has also suffered tough times. South Korea's intelligence agency said in 2015 Kim Yong Chol was demoted to a three-star general after dozing off during a meeting.
In 2016, Seoul's unification ministry said he was briefly sent to a re-education camp for his "overbearing" manner and abuse of power.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)
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