Chung Sung-yoon, an analyst at the Korea Institute for National Unification, said Kim Yong-chol would be the most senior North Korean official to step onto United States soil since Vice Marshall Jo Myong-rok met then-president Bill Clinton in 2000. Its demands could include a reduced United States military role in South Korea or an end to the American nuclear "umbrella" over South Korea and Japan.
Now his travel restrictions seem to have been further relaxed amid efforts to organise the Kim-Trump Summit in Singapore.
He will be the highest ranking North Korean official to visit the USA since 2000. It earlier reported that he was heading straight to Washington, but later said he changed his flight to NY.
He has played a central role in the recent thaw in relations between the North and South Korea, as well as the United States.
The meeting this time is likely to nail down the deal ahead of the summit, after it was cancelled due to a series of verbal provocations from the North, and then revived after a surprise meeting between Kim Jong-un and President Moon Jae-in, Saturday.
The two diplomats have crossed paths several times in the past, especially during the six-party negotiation process.
The U.S. reportedly demanded that North Korea dismantle nuclear warheads, nuclear materials, and missiles promptly or ship them overseas.
"The discussions are just getting started, so we are still waiting to see how they come out, but depending on their outcome, the president could join President Trump and Chairman Kim in Singapore", the official told Yonhap News Agency, while speaking on condition of anonymity.
And during his tenure as a senior intelligence official, Kim was accused by South Korea of masterminding deadly attacks on a South Korean navy ship and an island in 2010, and was linked by U.S. intelligence to a cyberattack on Sony Pictures in 2014. In response to reporters' questions regarding the report, South Korea's defense ministry said it does not have plans to change joint exercise schedules with the United States military.
Trump last week said he was pulling out of the scheduled June 12 meeting in Singapore, citing North Korea's "open hostility", but then said the talks could still happen.
Kim Jong Un's de facto chief of staff, Kim Chang Son, meanwhile, flew to Singapore via Beijing on Monday night, Japanese public broadcaster NHK reported.
North Korea claims to have destroyed its primary nuclear test site.
During that period North Korea ramped up its hacking programmes, including a hugely costly penetration of Sony Pictures that was seen as an attempt to stop the release of an American comedy film poking fun at the Kim Jong Un regime.
This was the second meeting between Moon and Kim Jong Un in the village, where they previously signed the Panmunjom Declaration on April 27, which details the denuclearization of the Koreas - one of the main talking points of the expected summit.
Kim Yong Chol would become the highest-ranking official from the isolated nation to visit the US since 2000, when Pyongyang sent Vice Marshal Jo Myong Rok to meet then-President Bill Clinton. In a tweet, Trump confirmed that Kim was heading for the United States.
He is widely believed to have masterminded the attack on a South Korean naval corvette, the Cheonan, in 2010, leading to the deaths of 46 sailors.
He and his team met Monday with a North Korean team led by Choe Son-hui, a vice foreign minister who has specialized in dealing with the United States, in the Tongilgak building on the northern side of Panmunjom, about the planned summit between their leaders.
He "will be authorized to speak on behalf of Kim Jong Un, and his intricate knowledge of the various policy issues at play means that USA officials will regard what he says as a bellwether for the DPRK's intentions at the summit". Moon has insisted Kim can be persuaded to abandon his nuclear facilities, materials and bombs in a verifiable and irreversible way in exchange for credible security and economic guarantees.