Nearly four years after Kim Jong Un announced the closure of the site, commercial satellite images show that construction activity has resumed at North Korea’s nuclear test ground. He invited foreign journalists to witness the destruction of the tunnels in preparation for his first summit with President Donald Trump.

Analysts believe it is unclear how long it will take North Korea, if at all, to restore the site for nuclear explosions. In the country’s northeast, Punggye-ri was used for its sixth nuclear test in 2017.

This is despite a diplomatic freeze that has been erupting since February 2019’s collapse of the Kim-Trump second meeting, when North Korea rejected major sanctions relief in return for partial surrender of its nuclear capability.

North Korea used the pause in talks for further expansion of its military capabilities. This includes nine rounds in missile launches in 2022. This unusually rapid pace is indicative of an intent to pressurize the Biden administration. Although they have offered open-ended negotiations, they have not shown any willingness to accept sanctions.

Kim presided over the January Workers’ Party meeting. Politburo members decried what they called U.S. hostility. They also threatened to resume nuclear explosives and long range missile tests that Kim had unilaterally suspended in 2018 in order to make diplomatic space with Trump.

Experts believe Kim is using an old strategy of brinkmanship in order to win concessions from Washington and his neighbours as he struggles with an economy that has been crippled by mismanagement, the pandemic and persistent U.S.-led sanctions.

The first report on the new Punggye-ri construction was made in an analysis of satellite imagery from Maxar Technologies by Jeffrey Lewis, Dave Schmerler and the James Martin Center for Nonproliferation Studies of the Middlebury Institute of International Studies.

Two new structures were seen in satellite photos taken by Planet Labs PBC and analyzed Tuesday afternoon by The Associated Press. They appeared to have been constructed to the site’s southern side between February-early March. These images were taken March 6, two days after Lewis and Schmerler’s Maxar images.

Analysts stated that the construction work was their first sighting of the site since May 2018, when North Korea invited foreign journalists to witness the destruction of tunnels at this site. The North Korean government didn’t invite any outside experts to verify what was destroyed.

Lewis and Schmerler noted that they see “very early signs of activity on the new site,” including construction of a building and repair of another building. They also wrote that there is some lumber and sawdust. “North Korea uses substantial amounts of wood at this site for both buildings and to shoring up tunnels. These changes occurred in the last few days.

Analysts said this indicates that North Korea has taken a decision on the status of the site, and may be planning to restore it to readiness for nuclear testing.

They wrote that “The test site is still many months away from being ready for North Korea’s nuclear explosions there.”

“How long it would take North Korea for them to restart explosive testing at this site will depend on how much damage has been done to the tunnels, which we don’t know with confidence. It is possible that North Korea may resume nuclear testing at another site.

According to some South Korean analysts, North Korea may resume nuclear testing in the next months. This would be a significant move for the Biden administration which has been focused on Russia’s increasing invasion of Ukraine and a potential confrontation with China.

The U.S. intelligence agency’s annual threat assessment was published Tuesday. It also warned of a possible North Korean nuclear test this year.

The assessment stated that “In January, North Korea started laying the foundations for an increase in tensions which could include (intercontinental missile or possibly a nuke test this year) actions that Pyongyang had not taken since 2017”.

North Korea flew this year a hypersonic missile to avoid regional missile defense systems. Experts believe that North Korea could use another nuclear test in order to prove it is capable of producing a small nuclear warhead small enough for the missile.

After North Korea’s latest rocket launch on Saturday, , which it claimed was connected to technology for a spy satellite, South Korea’s presidential office said that Seoul closely monitors Punggye-ri and other North Korean missile and nuclear facilities.

South Korea’s military claimed it fired warning shots at the North Korean patrol boat, which temporarily crossed the countries’ disputed western sea border while pursuing an unarmed North Korean vessel.

On Tuesday morning, the North Korean patrol boat crossed what is known as the Northern Limit Line. It was pursuing the vessel in waters close to South Korea’s Baekryeong Island. The boat then retreated after a South Korean naval vessel fired warning shots.

South Korean military officers seized the North Korean vessel that was being pursued by the patrolboat and began questioning its seven crewmembers.

The South Korean navy has fired warning shots many times to deter North Korean vessels from crossing their poorly marked maritime border. However, there have also been deadly clashes in the past. South Korea claimed North Korea was responsible for the attack on a South Korean warship in 2010 that resulted in 46 deaths, but the North denies responsibility.

Since the 1950-53 Korean War, South Korea has been patrolling the waters around the Northern Limit Line for many decades. The line is not recognized by North Korea, which insists on a boundary that extends deeply into the waters controlled by the South.

This happened just days before South Koreans voted in a closely contested presidential election. Clashes between major candidates have marked the bitter campaign. They argued over whether South Korea should keep engaging with North Korea or take a more aggressive line to stop its nuclear threat. Reporting from Dubai, United Arab Emirates by ___ Gambrell