North Korean officials “dangled” a historic meeting with the US vice-president Mike Pence during the Winter Olympics but pulled out at the last minute, the White House claimed on Tuesday.

The face-to-face encounter in South Korea would have been the first between senior officials from the Donald Trump administration and Pyongyang, which are in a standoff over Kim Jong-un’s pursuit of nuclear missiles that threaten the US mainland.

“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 Pence’s chief of staff, Nick Ayers.

But after Pence condemned human rights violations in North Korea and announced the toughest economic sanctions yet, the plan collapsed. Ayers added: “This administration will stand in the way of Kim’s desire to whitewash their murderous regime with nice photo-ops at the Olympics. Perhaps that’s why they walked away from a meeting or perhaps they were never sincere about sitting down.”

Among those that Pence was poised to meet on 10 February was Kim Jong-un’s younger sister, Kim Yo-jong, and the nominal head of state, Kim Yong-nam.

During the games, Pence was seated just feet away from Kim Yo-jong but they did not converse. The vice-president explained last week: “I didn’t avoid the dictator’s sister, but I did ignore her. I didn’t believe it was proper for the United States of America to give her any attention in that forum.”

North Korea has not carried out any weapons tests since it shot off its biggest intercontinental ballistic missile last November. Kim Yo-jong invited South Korean president Moon Jae-in to Pyongyang to begin talks soon. This has, despite Trump’s “little rocket man” jibes at Kim’s expense, prompted speculation about dialogue between Washington and Pyongyang.

But Ayers said: “The president made a decision that if they wanted to talk, we would deliver our uncompromising message. If they asked for a meeting, we would meet. He also made clear that until they agreed to complete denuclearisation we weren’t going to change any of our positions or negotiate.”

Heather Nauert, a state department spokesperson, added: “The vice-president was ready to take this opportunity to drive home the necessity of North Korea abandoning its illicit ballistic missile and nuclear programs.

“At the last minute, DPRK officials decided not to go forward with 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.”

North Korea had no immediate response to the reports from Washington, the Associated Press reported, but North Korean officials had said previously they had no interest or intention of meeting with Pence in Pyeongchang during the Olympics.