North Korea has withdrawn its staff from a joint office with South Korea just north of the border, Seoul's Unification Ministry said on Friday.

The move is another setback for South Korea's efforts to reduce tensions with Pyongyang in the aftermath of a failed summit between the United States and North Korea.

What we know so far:

South Korean Vice Unification Minister Chun Hae-sung said Pyongyang had "notified the South they are pulling out of the liaison office."

North and South Korea opened the office is in the town of Kaesong just north of the border in September amid efforts to promote closer ties.

Pyongyang did not give a reason for the decision.

Read more: North Korea mulls suspending denuclearization talks with US, diplomat says

South 'regrets' move

Chun said the order was "from an upper command" and did not violate any of the deals struck between both countries last year.

He added that Seoul "regretted" the withdrawal, but would "continue to work at the liaison office as usual."

Why is this a setback? South Korean President Moon Jae-In has tried to ease tensions with the North since assuming office in 2017 and the office was a symbol of friendly ties between the North and South.

Why was the liaison office created? Both Koreas staffed the office with representatives to ensure regular communication and coordination on joint projects.

ICBM threat and North Korea's overall military strength Major achievement In early June 2017, North Korea test-launched an intercontinental ballistic missile (ICBM) for the first time. Testing an ICBM marked a major military achievement for Pyongyang and a serious escalation of tensions with the United States and its allies in the region, particularly South Korea and Japan.

ICBM threat and North Korea's overall military strength Trouble with warheads At the time, defense experts said the ICBM could reach as far as the US states of Alaska and Hawaii. However, it was unclear if North Korea can field an ICBM capable of carrying a nuclear warhead on its cone that could survive reentry into the Earth's atmosphere. North Korean state media claimed the ICBM was capable of carrying a "large, heavy nuclear warhead" to any part of the United States.

ICBM threat and North Korea's overall military strength Pyongyang's nuclear tests - six times and counting The ICBM is believed to be a step forward in the North's nuclear program. Despite pressure from the international community, Pyongyang has made no secret of its nuclear ambitions. Alongside its ritual ballistic missile tests, North Korea has conducted nuclear tests on at least six occasions, including one in September 2017.

ICBM threat and North Korea's overall military strength US running out of patience? Responding to the first ICBM test with a show of force, the US and South Korean troops on conducted "deep strike" precision missile drills using Army Tactical Missile System (ATACMS) and the Republic of Korea's Hyunmoo Missile II. In April, the US sent its Carl Vinson aircraft carrier towards the Korean Peninsula, saying it was taking prudent measures against the North.

ICBM threat and North Korea's overall military strength Testing the boundaries Ignoring international condemnation, Pyongyang test-launched another rocket on July 28, 2017, just weeks after its first ICBM test. In both of the tests, North Korea used Hwasong-14 missile, but the second one reached a higher altitude and traveled a larger distance than the first one, according to the state media.

ICBM threat and North Korea's overall military strength Whole of US within range? Pyongyang conducted its third test November 29, using a newly developed Hwasong-15 missile. US, Japanese and South Korean officials said it rose to about 4,500 km (2,800 miles) and flew 960 kilometers (600 miles) over about 50 minutes before landing in Japan's exclusive economic zone off the country's coast.

ICBM threat and North Korea's overall military strength One of the world's largest militaries Apart from a developing missile and nuclear program, North Korea has a powerful army with 700,000 active troops and another 4.5 million in the reserves. It can call upon almost a quarter of its population to serve in the army at any given time. The North's bloated army is believed to outnumber its southern neighbor's by two-to-one.

ICBM threat and North Korea's overall military strength Vast capabilities According to the 2017 Global Firepower Index, the North has, as part of a far-reaching arsenal, 458 fighter aircraft, 5,025 combat tanks, 76 submarines, and 5,200,000 total military personnel. The picture above from 2013 shows leader Kim Jong Un ordering strategic rocket forces to be on standby to strike US and South Korean targets at any time.

ICBM threat and North Korea's overall military strength Enemies all around Alongside the United States, Pyongyang views its neighbors South Korea and Japan as its two other main enemies. North Korea has used US military exercises in the region as means of galvanizing its people, claiming that the exercises are dress rehearsals for an impending invasion.

ICBM threat and North Korea's overall military strength Huge, colorful demonstrations of military might Every year, hundreds of thousands of soldiers and citizens roll through the streets of the capital Pyongyang to take part in the North's military parades. Preparations for the rallies often begin months in advance, and the parades usually mark important anniversaries linked with the Communist Party or Kim Jong Un's family.



amp/rt (AFP, Reuters, AP)

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