North Korea claims to have demolished nuclear test site

Kim Jong-un made good on his promise to demolish North Korea's nuclear test site, which was formally closed in a series of huge explosions Thursday as a group of foreign journalists looked on.

The development was overshadowed a few hours later by the decision of U.S. President Donald Trump to cancel a planned summit on June 12 in Singapore with Kim. Trump left the door open for future talks if North Korea re-engaged i constructive dialogue.

The explosions at the nuclear test site deep in the mountains of the North's sparsely populated northeast were centred on three tunnels at the underground site and a number of buildings in the surrounding area.

North Korea held a closing ceremony afterward with officials from its nuclear arms program in attendance. The group of journalists who witnessed the demolition, which touched off landslides near the tunnel entrances and sent up clouds of smoke and dust, included an Associated Press Television crew.

North Korea's state media called the closure of the site part of a process to build "a nuclear-free, peaceful world" and "global nuclear disarmament."

"The dismantling of the nuclear test ground conducted with high-level transparency has clearly attested once again to the proactive and peace-loving efforts of the [North Korean] government being made for assuring peace and stability on the Korean Peninsula and over the world," the North's official news agency reported late Thursday.

Impressive, but questionable, display

The North's decision to close the Punggye-ri nuclear test site has generally been seen as a welcome gesture by Kim to set a positive tone ahead of the summit. In a statement earlier Thursday, South Korea's National Security Council called the closing the North's "first measure toward complete denuclearization."

But it is not an irreversible move and would need to be followed by many more significant measures to meet Trump's demands for real denuclearization.

The North also did not invite international inspectors to the ceremony, which limits its value as a serious concession.

The event was, indeed, impressive.

The first blast the visiting journalists witnessed came at around 11 a.m. local time after they made a 12-hour plus trip by train and convoy through the night and over bumpy dirt roads. That explosion collapsed the complex's north tunnel, which was used for five nuclear tests between 2009 and last year.

Two other explosions, at around 2:20 p.m. and 4 p.m., collapsed the west and south tunnels, according to officials. North Korea's state media stressed that those two tunnels could have been used to carry out more tests at any time, countering reports that the Punggye-ri site had been rendered largely unusable after the six tests already conducted there.

Also blown up were observation posts and barracks used by guards and other workers at the facility. A tunnel on the eastern side of the facility had already been shut down after an initial nuclear test in 2006.

North Korea said the demolition of the facility did not cause any leakage of radioactive materials or have any "adverse impact on the surrounding ecological environment."

The journalists were allowed to stay at the site for about nine hours.

Getting to the remote site required an overnight train ride from Wonsan, a port city east of the capital, Pyongyang. In typically secretive fashion, officials instructed the media not to open the blinds that covered the windows of their train cars. They also were not allowed to shoot photos from the vehicles they took to the site from the nearest train station, about 20 kilometres away.

Libya comparisons irk North Korea

The demolition came as the North lobbed another verbal salvo at Washington, calling Vice-President Mike Pence a "political dummy" and saying it is just as ready to meet in a nuclear confrontation as at the negotiating table.

The outburst at Pence, issued in the name of a top Foreign Ministry official, comes on the heels of another sharp rebuke of Trump's newly appointed national security adviser, John Bolton, and has raised concerns that a major gap has opened between the two sides just weeks before the June 12 summit in Singapore.

In both cases, Pyongyang was trying to push back against hard-line comments suggesting North Korea may end up like Libya if it doesn't move forward quickly and irreversibly with concrete measures to get rid of its nuclear weapons.

Choe Son Hui, a vice minister of foreign affairs, was quoted Thursday by the North's state-run news agency slamming as "ignorant" and "stupid" comments Pence made in an interview with Fox News that compared the nuclear-capable North to Libya. Libya gave up its program at an early stage only to see its longtime dictator overthrown and brutally killed years later.

The summit plan hit a number of speed bumps recently as both sides have begun trading barbs and taking tougher positions. Trump met with South Korean President Moon Jae-in on Tuesday at the White House for consultations and suggested the summit could be delayed or even called off entirely.

A sitting U.S. president has never met face to face with the three members of the Kim family who have ruled North Korea for several decades, but hopes sprung up after a surprising chain of events in recent weeks.

Success in talks, should they eventually occur, would be a huge accomplishment for Trump. Meeting with the U.S. president as an equal on the world stage would be a major coup for Kim.