North Korean leader Kim Jong Un speaks during a meeting at the Inter-Korean Summit on Friday, April 27, 2018. (Inter-Korean Summit Press Corps )

SEOUL, South Korea — North Korea renewed its threat to boycott an upcoming summit with President Donald Trump, saying Thursday that it’s up to the United States to decide whether it wants to meet in a room or face a “nuclear-to-nuclear showdown.” The statement came as both sides are keeping the world in suspense over whether Trump and North Korean leader Kim Jong Un will go through with a summit planned for June 12 in Singapore. Trump raised doubt Tuesday when he said “there’s a very substantial chance” the meeting would not proceed as scheduled. He said Wednesday that it will be clear next week if the summit will occur, adding that “if we go, I think it will be a great thing for North Korea.” The North has stepped up its rhetoric as the summit date nears in what experts say is likely a maneuver to gain leverage in talks over its nuclear weapons program. A senior North Korean official took aim against Vice President Mike Pence for invoking the “Libya model” in an interview with Fox News on Monday. “I cannot suppress my surprise at such ignorant and stupid remarks gushing out from the mouth of the U.S. vice-president,” Choe Son Hui was quoted as saying Thursday by the state-run Korean Central News Agency. She called Pence a “political dummy,” pointing out that North Korea’s nuclear weapons program is far more advanced than the one that Libyan leader Moammar Gadhafi surrendered in the early 2000s in exchange for sanctions relief. Gadhafi was later killed at the hands of a mob after being ousted in an uprising supported by NATO airstrikes. North Korea has pointed to his fate as an example of why they need a nuclear arsenal, which the communist state insists is for self-defense. Pence reiterated a point made earlier by Trump. "There was some talk about the Libyan model last week, and you know, as the president made clear, this will only end like the Libyan model ended if Kim Jong Un doesn't make a deal," he said Monday on Fox News. Choe, a vice foreign minister who was previously the regime’s main point person for relations with the United States, warned that such comments could prompt her to suggest reconsidering the summit. “We will neither beg the U.S. for dialogue nor take the trouble to persuade them if they do not want to sit together with us,” she said. “Whether the U.S. will meet us at a meeting room or encounter us at nuclear-to-nuclear showdown is entirely dependent upon the decision and behavior of the United States.” North Korea already pulled out of high-level talks with the South at the last minute earlier this month to protest Seoul’s participation in joint Air Force drills with the United States known as Max Thunder, which are due to end Friday. The U.S. military altered the route of a scheduled flight of nuclear-capable B-52 bombers it said were part of a separate mission last week so that they would not fly over the Korean Peninsula, U.S. officials said on condition of anonymity because they weren’t authorized to release the information. The Air Force said only that the pair of Stratofortress bombers were deployed as part of the U.S. “continuous bomber presence mission” in the region. The pair of B-52s took off from Andersen Air Force Base on May 16 and participated in a “routine training mission” with Japanese fighter jets “in the vicinity of Japan,” spokeswoman Lt. Col. Lori Hodge said in an email. She said the U.S. coordinates with allies on the missions but declined to comment on the decision-making process out of operational security reasons. Pyongyang also threatened on May 15 to withdraw from the summit if the U.S. insists on what it called unilateral measures toward disarmament. The criticism underscores fears that the two sides are far apart in their goals for talks just over two weeks before the summit is to take place. It would be the first-ever summit between a North Korean leader and a sitting U.S. president. Secretary of State Mike Pompeo said Wednesday that he's "very hopeful" the summit will happen but insisted it was “ultimately up to Chairman Kim.” The Trump administration has insisted it will seek the complete and verifiable denuclearization of North Korea, while Pyongyang wants a phased approach that may include incremental steps in exchange for concessions such as relaxed sanctions. Experts say it’s highly unlikely that the North would be willing to give up its arsenal after demonstrating strong progress with a series of missile and nuclear tests last year. South Korea, which held a landmark summit with the North on April 27, is scrambling to keep the diplomatic process on track. President Moon Jae-in met with Trump in Washington on Tuesday. The foreign ministry said it was analyzing Choe’s remarks and was “in close consultations with the U.S. and other relevant countries to make sure the goal of complete denuclearization agreed upon in the inter-Korean summit is achieved through … the summit between the North and the U.S.” The White House, meanwhile, was proceeding with preparations for the summit. It was sending an advance team to Singapore this weekend, spokesman Raj Shah said. A U.N. committee also granted the North Koreans an exemption from sanctions including travel bans and asset freezes to allow delegates may travel to Singapore, The Associated Press reported.Stars and Stripes reporter Yoo Kyong Chang contributed to this report.

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