South Korean Prime Minister Lee Nak-yon hosted the North Koreans for lunch Sunday before Moon's chief of staff, Im Jong-seok, hosted them for dinner ahead of the concert.
And Kim's sister, Kim Yo-jong, made history by becoming the first member of the North's ruling family to visit the South since the Korean War in the mid-20th century.
U.S. Vice President Mike Pence, who led a U.S. delegation to the Olympic Games, told reporters that he and Moon discussed the South Korean leader's meeting with Kim Jong Un's sister, adding he remains confident about Seoul's support for the pressure strategy.
Joseph DeTrani, former US special envoy for nuclear talks with North Korea, said Moon should make it clear to Kim that he wants to discuss the nuclear and missile issues at the summit.
"Moon should realize that offering economic benefits for symbolic North Korean gestures is not only ineffectual but would themselves risk being violations of United Nations resolutions", Klingner said.
The delegation, the highest-ranking to visit the South, concludes its visit later on Sunday having charmed and intrigued the South Korean public, but still faces deep scepticism over the North's sincerity towards improving relations.
Her presence helped the theme of Korean unity to dominate the opening ceremony as the two Koreas marched under one flag.
By also sending a youthful, photogenic individual who would surely draw worldwide attention at the Olympics, Kim might have also been trying to construct a fresher image of the country, particularly in face of US efforts to use the Olympics as an occasion to highlight the North's brutal human rights record.
Tag: Samsung Galaxy S9 Leaks
According to the trade-in site Galaxy S8 owners can now expect to get around £311 for their Galaxy S8 if it's good condition. The second image showing the Galaxy S9 mounted on the DeX Pad, also shows the handset to sport a 3.5mm headphone jack .
South Korea's former leader Kim Dae-jung, who won a Nobel Prize for what was dubbed a "sunshine policy" with the North, held the first summit with Kim Jong Il in 2000 in Pyongyang.
"We're going to continue to put all the pressure to bear economically and diplomatically, while preserving all of our military options to see that that happens", Pence said.
It was already known that Kim Yo Jong is an adviser to her brother; now many are interpreting her presence here - and the freedom with which she seems to behave - as new signs of the power she holds.
The latest North Korean diplomatic overture does not appear to have discouraged Washington from pursuing its strategy of pressure.
"If it leads to promises of aid, then it would definitely undermine the maximum pressure strategy", Gause said, referring to the proposed summit between the two Koreas.
The KCNA report cited Moon as saying inter-Korean relations should be mended by the parties concerned "at any cost as indicated by Chairman Kim Jong Un in his New Year Address".
Taekwondo athletes from North and South Korea produced a stunning demonstration in Gangwon as sporting diplomacy took center stage alongside kicking, screaming and flying planks of wood on Saturday. The U.S. -led worldwide community has been tightening the screws on North Korea with sanctions created to punish its economy and rein in its efforts to expand its nuclear weapons and missile program, which now includes developmental long-range missiles targeting the U.S. mainland. It was a sharp, but possibly fleeting, contrast with many months of rising tensions connected to the North's continued development of nuclear weapons and long-range missiles.