To complicate matters further, Kim Yo-jong, who oversees the North Korean regime's propaganda, is blacklisted under sanctions, while Pence will be accompanied by the father of Otto Warmbier, the American student who was imprisoned by North Korea and died shortly after returning to the U.S. in a coma past year.
But his comments did not rule out a meeting - and nor has Pence, who lambasted the North Thursday but added: "There may be a possibility for any kind of an encounter with North Koreans", whether informal or a meeting. "It's our Olympics and we can't wave the South Korean flag".
U.S. vice-president Mike Pence, who has described North Korea as the world's most tyrannical regime, spoke with Moon on Thursday ahead of the opening ceremony in the mountain resort of Pyeongchang, just 80km (50 miles) from the heavily armed border with the reclusive North.
Kim Jong Un, dressed in a long black winter coat, was shown walking on a red carpet with his wife at the beginning of the event, which North Korea's state-run television broadcast hours after it was over.
The usual accompaniments were present, namely intercontinental ballistic missiles to display Pyongyang's military capabilities.
Mr Moon is to have lunch on Saturday with North Korea's 22-strong delegation, which includes the titular head of state, Kim Yong-nam, and Kim Yo-jong, the powerful younger sister of leader Kim Jong-un.
And there is no prospect that Kim Yo Jong, who will attend the Olympics this weekend, will cross paths with US President Donald Trump's daughter Ivanka Trump, who will attend the closing ceremony a fortnight later. Pence is to be accompanied by the father of Otto Warmbier, the American student who was imprisoned by North Korea and died just days after being returned to the USA in a coma a year ago.
Defense Secretary James Mattis, in a press conference Wednesday, told reporters, "Vice President Pence is quite capable of making the call on that there, while he's in Korea", when asked about a potential meeting.
"We have never begged for dialogue with the USA and will be the same in the future", said Cho Yong-sam, director-general of the North American department of North Korea's foreign ministry, according to Korean news outlet Yonhap and translated by ABC News.
North Korea has sent hundreds of people to the Olympics in the South, including officials, athletes, artists, journalists and a 230-member cheering group.