WASHINGTON, SEOUL - Diplomatic activity gathered pace ahead of a planned June 12 summit in Singapore between North Korean leader Kim Jong Un and President Donald Trump as high-level aides on both sides crossed oceans to meet their counterparts in preparation for the historic meeting.
Top North Korean General Kim Yong Chol, long a key aide to leader Kim Jong Un, was due to arrive in the United States for what would be the highest-level visit in years. He will meet Secretary of State Mike Pompeo later this week, said the White House.
In the meantime, North Korean officials led by Vice-Foreign Minister Choe Son Hui met US officials led by US Ambassador to the Philippines Sung Kim - possibly the State Department's top Korea expert - at the North-South border. They will have additional meetings this week.
North Korean officials also arrived in Singapore to meet an American team led by Mr Joe Hagin, deputy chief of staff for operations at the White House, and deputy national security adviser Mira Ricardel.
Mr Kim Chang Son, leader Kim Jong Un's de facto chief of staff, flew in on Monday night, but bypassed reporters waiting at Changi Airport Terminal 3. He is said to have been received by Singapore Foreign Ministry officials, including Permanent Secretary Chee Wee Kiong, and taken through VIP channels.
Mr Ko Young Hwan, the first North Korean diplomat to defect from the North, said on cable TV Channel A that Mr Kim Chang Son, as Mr Kim Jong Un's "shadow", keeps a low profile and avoids the media spotlight.
On Tuesday (May 29), he was spotted getting into a black Mercedes-Benz car at the Fullerton Hotel, while his entourage boarded a minivan.
US officials were also seen at a hotel on Sentosa, but declined to comment, reported Reuters. Mr Hagin and his team arrived on Monday via the US Yokota Air Base in Japan.
"We have put a great team together for our talks with North Korea. Meetings are currently taking place concerning Summit, and more," President Trump tweeted on Tuesday. "Solid response to my letter, thank you!"
Gen Kim, who accompanied Mr Kim Jong Un at his recent meetings with both Chinese President Xi Jinping and South Korean President Moon Jae In, knows Mr Trump's daughter and top aide, Ms Ivanka Trump. He sat next to her during the closing ceremony of the Winter Olympics in the South Korean resort of Pyeongchang - an ice-breaking event that changed months of hostile rhetoric to a tentative detente paving the way for talks.
On Tuesday, White House press secretary Sarah Huckabee Sanders said Mr Trump will meet Japanese Prime Minister Shinzo Abe on June 7 at the White House. The leaders spoke on the phone on Monday, planning to meet before the Singapore summit.
Ms Sanders also said National Security Adviser John Bolton has had phone calls with his South Korean and Japanese counterparts almost every day over the last few weeks.
The US postponed imposing new sanctions on North Korea as it tries to get the summit back on track, according to a report in The Wall Street Journal citing official sources.
Japan's Foreign Ministry on Tuesday, however, reported to the United Nations a suspected sanctions violation by Pyongyang, when a military patrol plane spotted a North Korean tanker apparently involved in a cargo transfer with a small vessel of unknown nationality.
"The (Japanese) government strongly suspects they were transferring goods, which is banned by UN sanctions," said the ministry.