Updated 11.57 am

SOUTH KOREA BELIEVES the North has successfully miniaturised a nuclear weapon to fit onto a missile, Seoul’s defence minister said today.

“We believe it fits in an intercontinental ballistic missile,” Song Young-Moo told lawmakers at a parliamentary briefing, a day after Pyongyang’s biggest nuclear test to date.

Pyongyang claimed that the nuclear test was the successful detection of a hydrogen bomb.

The test has dramatically ratcheted up tensions in the region with Seoul also saying it believes North Korea could be preparing another missile launch.

South Korea also fired an early-morning volley of ballistic missiles in an exercise simulating an attack on the North’s nuclear test site.

The United States also warned it could launch a “massive military response” to any threats from North Korea following Pyongyang’s provocative detonation.

Defense Secretary Jim Mattis spoke out after North Korea carried out an unexpectedly strong nuclear test, more powerful than the bomb that levelled Hiroshima in 1945.

President Donald Trump called an emergency meeting of his national security advisers and had his second telephone call of the weekend with Japanese Prime Minister Shinzo Abe, but did not talk to South Korea’s Moon Jae-In, instead accusing Seoul of “appeasement”.

He threatened drastic economic sanctions, including “stopping all trade with any country doing business with North Korea.”

US monitors measured a powerful 6.3-magnitude earthquake near the North’s main testing site yesterday, felt in parts of China and Russia, with an aftershock possibly caused by a rock collapse.

North Korea — which in July carried out two intercontinental ballistic missile (ICBM) launches that apparently brought much of the US mainland into range — hailed its test of what it described as a hydrogen bomb designed for a rocket as “a perfect success.”

Mattis told reporters:

Any threat to the United States or its territories, including Guam, or our allies will be met with a massive military response, a response both effective and overwhelming.

“We are not looking to the total annihilation of a country, namely North Korea,” he added, but warned:

We have many options to do so.

South Korean tanks on exercise n Paju, South Korea. Ahn Young-joon / PA Images Ahn Young-joon / PA Images / PA Images

The White House said the US was committed to “defending our homeland, territories, and allies using the full range of diplomatic, conventional, and nuclear capabilities at our disposal.”

‘Fratricidal war’

Pyongyang residents celebrated as a jubilant television newsreader hailed the ”unprecedentedly large” blast which she said had moved the country closer to “the final goal of completing the state nuclear force.”

It prompted an international chorus of condemnation, including from both the North’s key allies, China and Russia.

UN Secretary General Antonio Guterres condemned the test as “profoundly destabilising”. The Security Council will hold an emergency meeting today.

South Korean President Moon Jae-In, who advocates engagement as well as penalties to bring Pyongyang to the negotiating table, called for new United Nations sanctions to “completely isolate North Korea.”

Seoul today carried out a live-fire exercise in the Sea of Japan, which it calls the East Sea, using a volley of missiles to simulate an attack on the North’s nuclear site.

But Trump criticised the US treaty ally on Twitter, saying: “South Korea is finding, as I have told them, that their talk of appeasement with North Korea will not work, they only understand one thing!”

In a statement, the presidential Blue House retorted: “Korea is a country that experienced a fratricidal war.”

It “will continue to push for the denuclearisation of the Korean Peninsula through peaceful means working together with our allies”, it added.

‘Cut off North Korea’

Hours before the test, the North released images of Kim at his country’s Nuclear Weapons Institute, inspecting a device it called a “thermonuclear weapon with super explosive power” entirely made “by our own efforts and technology,” according to the Korean Central News Agency.

An image released by North Korea purportedly shows Kim Jong Un inspecting the nuclear device. PA Images PA Images

A series of US and United Nations-backed sanctions seem to have had little effect on Pyongyang.

US Treasury Secretary Steven Mnuchin said yesterday that his department was preparing potent new measures that would “cut off North Korea economically.”

The measures would ensure that “anybody that wants to do trade or business with them will be prevented from doing trade or business with us,” he said on “Fox News Sunday.”

While the United States has virtually no trade with the North, the burden of such sanctions would fall heavily on China, which buys about 90% of North Korean exports.

 Tremor felt in China, Russia

South Korean experts said the tremor near North Korea’s main test site was five to six times stronger than that from a 10-kiloton test a year ago.

Despite fears of a possible radioactive leak, Japanese and Chinese scientists said they had detected no radiation in the atmosphere.

As well as July’s landmark ICBM tests, Pyongyang last week fired a missile over Japan.

Trump has warned Pyongyang that it faces “fire and fury” and that Washington’s weapons are “locked and loaded.”

But the North has huge artillery forces within range of Seoul, a city of 10 million people, and could inflict mass casualties in retaliation to any strike.

“There are no realistic military options in terms of striking North Korea, because doing so would likely spark a full-scale war,” Mark Fitzpatrick of the International Institute for Strategic Studies, told AFP.

© – AFP 2017

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