A South Korean soldier walks past a television screen showing pictures of US President Donald Trump (L) and North Korean leader Kim Jong Un at a railway station in Seoul on March 9, 2018.

A cargo plane which accompanied North Korean leader Kim Jong Un on his recent visit to China departed Pyongyang and was likely headed for Singapore on Sunday, ahead of Kim's summit with U.S. President Donald Trump.

Kim is due to meet Singapore Prime Minister Lee Hsien Loong in the city-state later on Sunday, Singapore's ministry of foreign affairs said in a statement. Kim flew into Changi airport on Sunday, multiple outlets reported.

Trump will meet with Lee on Monday. He is scheduled to arrive at Singapore's Paya Lebar Airbase at 8:35 p.m. on Sunday and go to the Shangri-La Hotel, according to the White House.

His delegation onboard Air Force One includes Secretary of State Mike Pompeo, National Security Advisor John Bolton, White House Chief of Staff John Kelly and White House Press Secretary Sarah Sanders.

Kim had taken only one known overseas trip by air since becoming leader in 2011 and the Ilyushin-76 cargo plane accompanied his personal Ilyushin-62M jet to Dalian in China in May.

An Il-76 departed Pyongyang early on Sunday and stopped in Guangzhou in southern China before being airborne again likely headed for Singapore, flight tracking services showed.

Refrigerator trucks were set to wait at Changi Airport on Sunday to receive the cargo flight, Singapore's Straits Times newspaper reported, saying the plane is believed to be carrying food items as well as several luxury cars to escort the North Korean leader.

The Il-76 cannot fly more than 3,000 km (1,860 miles) without refueling if carrying a full load. It was expected to stop off at a friendly location on the way to Singapore, which is 4,700 km (2,920 miles) from Pyongyang's Sunan airport, or fly with a reduced load.

The Il-76, originally designed for moving heavy machinery to remote parts of the Soviet Union, is big enough to fit a school bus or two shipping containers inside it, according to passenger and cargo flight operator Antarctic Logistics & Expeditions.

—CNBC contributed to this report.