Donald Trump has said he has received a "nice" letter from Kim Jong-un and he looks forward to meeting him "soon", as the United States president thanked the North Korean leader for handing over possible remains of American soldiers killed in the Korean War.
Fifty-five cases of what are believed to be the remains of Americans who were killed or captured during the Korean War were transported to a military base in Hawaii, after they were handed over to US officials who had travelled to North Korea last week.
"Thank you to Chairman Kim Jong Un for keeping your word & starting the process of sending home the remains of our great and beloved missing fallen! I am not at all surprised that you took this kind action. Also, thank you for your nice letter - I look forward to seeing you soon!" Trump tweeted.
The repatriation of US remains was agreed by the two leaders during their historic June 12 summit in Singapore.
More than 8,000 American soldiers are missing from the 1950-53 Korean War.
In his tweet, Trump also thanked the young North Korean leader for his "nice letter", without elaborating.
Later the White House Press Secretary Sarah Sanders said that Trump received the letter from Kim on August 1.
"A letter to President Trump from Chairman Kim was received on August 1. The ongoing correspondence between the two leaders is aimed at following up on their meeting in Singapore and advancing the commitments made in the US-DPRK joint statement," Sanders said.
DPRK stands for Democratic People Republic of Korea, which is more popular as North Korea.
During the summit, President Trump had hinted the possibility of an invitation to Kim to visit him at the White House.
Last month, North Korean state media reported that Kim had accepted Trump's invitation to visit the US.
No date for a visit has been announced.
But critics question whether the two leaders' bilateral meetings will yield its promised objective of "complete denuclearisation of the Korean Peninsula".
US spy satellites have detected fresh activity at the North Korean facility that produced its first intercontinental ballistic missiles.
Last week, US Secretary of State Mike Pompeo told senators that North Korea was continuing to produce fuel for nuclear bombs.