The conservative South Korean newspaper Chosun Ilbo reported Friday that North Korean dictator Kim Jong-un will have to borrow a foreign plane to reach the planned summit between himself and President Donald Trump scheduled for Tuesday.

An unnamed “diplomatic source in Seoul” confirmed to the newspaper that Kim’s official airplane could only make the flight from Pyongyang to Singapore for the meeting with a refueling stop in China, which international media outlets speculated for months would be embarrassing to the dictator.

“North Korea originally considered a refueling stop in China, but chose to fly straight to Singapore,” the source reportedly said. “There was some trepidation about flying the 4,800 km distance aboard Kim Jong-un’s own aging plane, so a third country is expected to supply it.”

Chosun Ilbo says Singapore and China are the likeliest donors of a functional plane to carry Kim and his sister Kim Yo-jong, to the summit, and that discussions between Kim and Singaporean Foreign Minister Vivian Balakrishnan in Pyongyang this week in part involved the logistics of physically getting Kim to the tropical Asian country.

The news that Kim Yo-jong, believed to be the head of North Korea’s Propaganda and Agitation (or state media) Department, will join her brother in meeting Trump suggests that Kim will be putting his most diplomatic face forward. Kim Yo-jong, while running arguably the most belligerent state media organization in the world, made a notable diplomatic impact in South Korea, meeting South Korean President Moon Jae-in and paving the way for a summit between her brother and Moon.

Kim Jong-un made his first known international flight as head of state last month to Dalian, China, a beachside resort town, to meet Communist Party leader Xi Jinping in preparation for next week’s summit. Kim made his first foreign visit as leader of North Korea in March to Beijing, on that occasion traveling by train.

Following the Dalian trip, the BBC identified Kim’s aircraft as a “Soviet-made long-range aircraft, the Ilyushin-62 (Il-62),” the same plane that flew his family and top officials to PyeongChang, South Korea, in February for the Winter Olympics. The plane is not known to have ever successfully made a long-distance flight, which Chosun notes aroused some concerns in Pyongyang about Kim flying it over water to reach Singapore.

North Korea has a national airline, Air Koryo, but neither Kim’s father nor grandfather – the dictators Kim Jong-il and “eternal president” Kim Il-sung – were known to have flown it.

Prior to the Dalian visit, and before both sides announced Singapore as the venue for the historic meeting, media outlets speculated over whether Kim had the ability to fly to a neutral venue. The New York Times noted that experts were not sure whether “Mr. Kim’s fleet of Soviet-era planes can fly him more than a few thousand miles from North Korea,” limiting the options for a visit.

“Could Mr. Kim borrow a plane?” the newspaper asked. “Perhaps, but not without a significant dent to his well-established hubris.”

“We used to make fun of what they have – it’s old stuff,” former CIA analyst Sue Mi Terry told the Washington Post at the time. “We would joke about their old Soviet planes.” Experts agreed that Kim’s plane could not survive a full flight across the Pacific, restricting his ability to travel to the United States. North Korea had reported invested in transcontinental missiles, but not transcontinental airplanes.

In addition to concerns about transportation, several reports indicate that Kim is concerned that leaving the country could expose him to assassination. Sources speaking to Bloomberg this week noted that American officials have reason to believe “Kim is extremely worried about security at the summit and is fearful of assassination attempts.” Singaporean Foreign Minister Vivian Balakrishnan also reportedly discussed security with Kim in Pyongyang on Thursday.

President Trump has described the summit as a “getting-to-know-you plus” endeavor, telling reporters during a joint press conference with Japanese Prime Minister Shinzo Abe on Thursday, “it’s gonna be much more than a photo-op.”

“I think it’s not a one meeting deal. It would be wonderful if it were,” he added, describing the meeting as “fruitful” and “exciting.”

Kim and Trump are scheduled to meet at 9 a.m. local time on Tuesday, June 12, in Singapore.