North Korea launches its largest ever nuclear test

Seoul : North Korea has confirmed it has conducted its most powerful nuclear test to date, marking the 68th anniversary of its founding with a reminder to the world that it may be edging closer to developing a warhead capable of striking the US mainland.

Friday morning’s test, which triggered a magnitude 5.3 earthquake, drew immediate condemnation from North Korea’s neighbours and Washington.

Barack Obama, who was briefed on board Air Force One by National Security Adviser Susan Rice as he returned to the US from an Asian tour, said provocative actions by North Korea would have “serious consequences.”

“To be clear, the United States does not, and never will, accept North Korea as a nuclear State,” Obama said in a later statement.

North Korea, which labels the South and the United States as its main enemies, said its “scientists and technicians carried out a nuclear explosion test for the judgment of the power of a nuclear warhead,” according to its official KCNA news agency.

It said the test proved North Korea was capable of mounting a nuclear warhead on a medium-range ballistic missile, which it last tested on Monday when Obama and other world leaders were gathered in China for a G20 summit.

The test was conducted at a known testing site in Punggye-ri in the country’s northeast and produced a slightly higher yield than that recorded after its third nuclear test, in 2013, previously considered it most powerful to date. The test’s estimated yield of 10 kilotonnes is higher than any of the North’s previous four controlled nuclear detonations, according to experts.