We’ve all been there—you make vague plans with someone to be polite, then they unexpectedly accept and you actually have to go through with it. The man who led U.S. diplomatic efforts in North Korea until this year has said Kim Jong Un’s officials were “surprised” when Donald Trump accepted their proposal of a summit in the next few months. “To be frank with you, I think they were a little bit surprised that Washington, President Trump, readily accepted,” Ambassador Joseph Yun, who stepped down last month, told CNN, adding: “They thought it would take a little time.” However, Yun said he was pleased when Trump announced last week that he would meet with Kim. “I’m very supportive of [Trump’s] decision to engage at the highest levels—that is a great outcome,” said the former ambassador. Meanwhile, new satellite imagery examined by Western experts has revealed new activity in North Korea’s nuclear reactors, though it’s unknown if the activity is related to generating power or the country’s weapons program.