Washington (CNN) US Vice President Mike Pence was set to meet with North Korean officials, including Kim Jong Un's sister, during his politically charged visit to the Winter Olympics in South Korea earlier this month, his office confirmed on Tuesday.

But the North Koreans pulled out of the meeting before it could happen. Pence's office said they believed the abrupt cancellation was a sign that US attempts to exert pressure on the regime were working.

"North Korea dangled a meeting in hopes of the vice president softening his message, which would have ceded the world stage for their propaganda during the Olympics," said Nick Ayers, Pence's chief of staff.

President Donald Trump had signed off on the decision to meet, with the caveat that the United States wouldn't back off its stated demand that Pyongyang abandon its nuclear weapons.

North Korea sent a 500-strong delegation to the games made up of athletes, cheerleaders, domestic media and high-ranking government officials -- including Kim Yo Jong, the sister of North Korea's leader and head of the country's propaganda department, and Kim Yong Nam, North Korea's ceremonial head of state.

Their attendance was the result of diplomatic negotiations earlier this year between Seoul and Pyongyang, the first high-level talks in more than two years.

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A close encounter

Pence and his wife were seated just feet away from Kim Yo Jong and Kim Yong Nam on February 9 for the Games' opening ceremony.

Pence was due to meet with both of them the next day, but the North Koreans abandoned the plans shortly beforehand. The meeting was set to take place at the Blue House in Seoul, South Korea's equivalent to the White House, officials confirmed.

The US State Department said that Pence had been ready to "to drive home the necessity of North Korea abandoning its illicit ballistic missile and nuclear programs" at the meeting.

"We regret their failure to seize this opportunity. We will not apologize for American values, for calling attention to human rights abuses, or for mourning a young American's unjust death," Heather Nauert, State Department spokeswoman, said in a statement.

Vice President Mike Pence, second from the bottom right, sits between second lady Karen Pence, third from the bottom left, and Japanese Prime Minister Shinzo Abe at the Olympic Games' Opening Ceremony. Behind Pence are Kim Yong Nam, third from the top right, president of the Presidium of North Korean Parliament, and Kim Yo Jong, second from the top right, the sister of North Korean leader Kim Jong Un.

When he returned to the United States, Pence said that he chose to actively ignore Kim Yo Jong at the Opening Ceremonies because he "didn't believe it was proper for the United States of America to give any countenance or attention in that form to someone who's not merely the sister of the dictator but is the leader of the propaganda effort."

Hints at talks

Ahead of his arrival at the Olympics, Pence hinted at the possibility of a meeting, saying he hadn't ruled out meeting with North Korean officials.

Standing in front of an F-22 fighter jet at Elmendorf Air Force Base in Alaska, Pence said Trump "has said he always believes in talking, but I have not requested any meeting. But we'll see what happens."

At that point, plans were not yet finalized for the meeting, though Trump, Pence and other administration officials had agreed in theory to a sit-down with the North Koreans who were attending the Olympics.

North Korea's Foreign Ministry had said shortly before the Games began that it had no plans to meet with US officials during the delegation's visit to South Korea, according to comments carried by North Korea's state-run Korean Central News Agency.

Ayers, the vice president's chief of staff, said Pence's meeting with defectors and his decision to host the father of Otto Warmbier, an American who died after being detained by the North Koreans, led the North Korean officials attending the games to reconsider the planned meeting.

"North Korea would have strongly preferred the vice president not use the world stage to call attention to those absolute facts or to display our strong alliance with those committed to the maximum pressure campaign. But as we've said from day one about the trip: This administration will stand in the way of Kim's desire to whitewash their murderous regime with nice photo ops at the Olympics," Ayers said. "Perhaps that's why they walked away from a meeting or perhaps they were never sincere about sitting down."