The celebration typically starts July 27, a national holiday in North Korea called the "Victory in the Fatherland Liberation War".
"If Japan does not correct its ambitions regarding peace and security, it should realize the end result where Japan is passed over will be inevitable", The North's official Korean Central News Agency said Monday.
As well as the security operation, the Singapore government footed the bill for the delegation from the sanctions-hit North, including Kim's stay at the luxury St Regis hotel, according to the BBC.
Mintaro Oba, a former U.S. diplomat who focused on North Korea policy, said the cancellation was significant: "It tells us that North Korea has enough confidence in the staying power of engagement with the United States - for now - that they want to create a more positive atmosphere at home and send more constructive signals overseas".
Still, North Korea's handling of the changes and how it presents them to its people remains highly nuanced.
The meeting was the culmination of a rapid detente between Pyongyang and Washington and saw Kim commit to working towards denuclearisation, although critics noted the summit agreement was vague and non-binding.
Salah scores again amid dispute with Egyptian federation
The controversy stems from a photo that surfaced before the tournament began of Salah locking hands with Chechen Republic leader Ramzan Kadyrov .
State media referred to Trump quite deferentially in their reports of the summit, calling him by his full name and adding the title of president of the United States of America - itself a somewhat jarring contrast to the way it normally spits out merely the surname of U.S. officials, with no titles.
North Korea's decidedly less strident posture these days underscores the delicate position it finds itself in after decades of touting the United States as its archenemy. North Korea is estimated to have around 1,000 artillery pieces along the frontier, threatening much of the South's capital Seoul only 50km away.
Getting rid of all the anti-American propaganda would be a Herculean task.
The North has long accused the United States of provoking the 1950-53 Korean War as part of a plan for global domination and blames it for the division of the peninsula, agreed between Moscow and Washington in the closing days of World War II.
Get the Monitor stories you care about delivered to your inbox.
Kim has also stepped up attacks on capitalism, letting North Koreans know that while he's opening up diplomatic ties, he's not giving up socialism.
This story was reported by The Associated Press.