The remote site deep in the mountains of the North's sparsely populated northeast interior is expected to have a formal closing ceremony in the next day or two, depending on the weather.
Secretary of State Mike Pompeo says it is ultimately up to North Korean leader Kim Jong Un whether a planned summit with President Donald Trump takes place.
Trump has expressed suspicion that the North's recent barbs against the US were influenced by Kim's unannounced trip to China two weeks ago - his second in as many months.
"I can not suppress my surprise at such ignorant and stupid remarks gushing out from the mouth of the U.S. vice-president", vice-minister of Foreign Affairs Choe Son Hui said in a statement released by the state-run KCNA news agency.
US President Donald Trump warned Tuesday his landmark summit with Kim may be delayed, while insisting the North Korean leader was "serious" about denuclearization. The American people are counting on us to get this right. Each meal was $20.
Mr Trump later denied the United States would follow the "Libyan model" if an agreement was reached with North Korea. -South Korean military exercises.
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Sharif dispelled the notion that the comments were falsely attributed to him, saying that he will speak the truth come what may. He expressed full support for Sharif and said the entire party, including party president Shehbaz Sharif, stands with him.
South Korea asked the committee for similar exemptions that were granted for the North Korean delegations which attended the Winter Olympics in Pyeongchang in February. From the coastal city of Wonsan, all foreign journalists in North Korea boarded a special train at 7 p.m. for Punggye-ri, Newsis reported. The other journalists from the United States, the U.K., China and Russian Federation arrived in Wonsan on Tuesday. On Wednesday it was escorting a group of global reporters, including an Associated Press Television crew, to witness the closure of its atomic test site.
Trump is due to meet the North Korean dictator on June 12 in the Southeast Asian city-state.
"We will know next week about Singapore", he told reporters at the White House before leaving for NY, the day after acknowledging that there's a "very substantial chance" the summit will be canceled.
The U.S. wants a "rapid" process in which North Korea's abandonment of its nuclear program is "total and complete, that won't be extended over time", Pompeo said of the agenda for the planned summit.
If it goes ahead, it will be first meeting between a US and a North Korean leader during more than six decades of hostility, and it would come just months after the North's rapid progress toward attaining a nuclear-tipped missile that could strike America fueled fears of war.
By bringing in the foreign media, mainly television networks, the North is apparently hoping to have images of the closing - including explosions to collapse tunnel entrances - broadcast around the world.