The red-shingled, colonial-style Capella is a five-star hotel on Sentosa Island, which boasts several resorts, hotels, two golf courses and a theme park.

US and North Korean officials considered several other hotels in Singapore as potential locations for the summit, which will be the first meeting between a US and North Korean leader.

A top option from the beginning had been the Shangri-La hotel, a massive structure near Orchard Road that could be heavily secured while also providing an ornate setting. The hotel hosted a historic summit meeting between Chinese President Xi Jinping and Taiwanese leader Ma Ying-jeou in 2015.

US officials, led by Joe Hagin, the deputy White House chief of staff for operations, negotiated with a North Korean delegation last week to determine the location and time for the summit. Security had been a chief concern for the North Koreans during the discussions, sources told CNN.

The meetings often proceeded at a painstaking pace. North Korean officials are "sensitive to being dictated to," one source close to the talks said, and the Hagin-led team has taken pains to present ideas for the summit in a collaborative way.

"Even if you're leading a horse to water, you have to do it in a way that is collaborative," the source said.

North Korean officials in Singapore also needed to get sign-off on almost every detail with their superiors in Pyongyang, leading to one- or two-day intervals before they could reach an agreement on even minor logistical details, the source said.