A nuclear test would be a provocation that follows successive launches of intercontinental ballistic missiles capable of reaching the U.S. It would be the sixth nuclear test by Pyongyang since 2006 and the first since the U.S. and South Korea elected new leaders.
"If North Korea did indeed conduct a nuclear test, we absolutely can not tolerate and must protest firmly".
One expert said the size of Sunday's detonation, measured by the U.S. Geological Survey at magnitude 6.3, meant it was possible it could be a hydrogen bomb test.
North Korea conducted it's 4th and 5th nuclear tests in January and September of previous year.
South Korea and Japan are gathering and analyzing data to confirm details of the test, which Japanese Minister Shinzo Abe said could not be tolerated.
North Korea Reveals Shocking Images Of Possible H-Bomb Warhead
The hydrogen bomb test ordered by leader Kim Jong Un was a "perfect success" and was a "meaningful" step in completing the country's nuclear weapons program, state television said.
Donald Trump has reacted to what he's calling "a major Nuclear Test" by North Korea - branding the North "a rogue nation" whose "words and actions continue to be very hostile and dangerous" to the United States.
The announcement came amid heightened tensions after North Korea fired an intermediate-range ballistic missile over Japan last week.
There was no independent confirmation of the claims.
"That scale is to the level where anyone can say a hydrogen bomb test".
The U.S. on Thursday had sent the bombers and F-35 stealth fighters to the skies of South Korea in a show of force - and North Korea strongly protested. In July this year, it apparently conducted its first two intercontinental ballistic missiles tests.
Kim Jong Un, who visited the country's nuclear weapons institute, "watched an H-bomb to be loaded into new ICBM" and "set forth tasks to be fulfilled in the research into nukes", KCNA said.
South Korea's main spy agency has previously asserted that it does not think Pyongyang now has the ability to develop miniaturized nuclear weapons that can be mounted on long-range ballistic missiles.
The U.S. State Department had no immediate reaction.
The White House said Trump spoke with Abe regarding "ongoing efforts to maximize pressure on North Korea".
Ahead of the Bell: Economy-GDP
That's an annualized rate of expansion of 4.5 per cent, the highest the figure has been since the third quarter of 2011. The Bank of Canada had predicted second-quarter real GDP to expand by 3% in its latest forecast, released in July.
Outside experts said that it appeared to be a test of a boosted fission weapon, rather than an H-bomb. But if the North Korean program is advancing at the pace it claims, it may be too late to debate over negotiations or their meaning - the North may be closer than anyone expected to having a viable nuclear deterrent. He called on North Korea to "immediately cease all existing nuclear and ballistic missile activities in a complete, verifiable, and irreversible manner, and re-engage in dialogue with the worldwide community".
Conservative parties have called for Moon to rethink his dovish policy, demanding Seoul consider its own nuclear options, such as the redeployment of US tactical nuclear arms, which were withdrawn in the early 1990s following an inter-Korean declaration for a nuclear-free Korean Peninsula.
Can North Korea deliver a nuclear warhead?
"Our hydrogen fuel, which can be arbitrarily adjusted from tens of to hundreds of kilotons depending on the target of the nuclear strike, not only exerts enormous destructive power", but can also explode at a high altitude, producing a "super powerful EMP [electromagnetic pulse] against a vast region", it said.
China says sanctions won't help as Trump targets Venezuela
Maduro says the USA is seeking to stifle oil exports through sanctions and a "naval blockade" on the Latin American country. The new sanctions would also put more sway on the view that Venezuela is under military threat by President Trump.
The Cabinet reshuffle will be closely watched to gauge the message PM Modi wishes to send ahead of the 2019 General Elections. Besides, Uttar Pradesh is far too important a state electorally for the state party chief to juggle responsibilities.
Drama has grown between camp Swift and camp West over the years, from on-stage interruptions to leaked phone calls. Swift's new single sold around 200,000 downloads in the USA upon release, according to Billboard .
From the beginning, Greywind says she suspected her daughter had been harmed - a suspicion that tragically proved true. Crews and Hoehn were arrested on Thursday and initially were each facing a Conspiracy to Commit Kidnapping charge.
At Alamo Square Park and elsewhere in the city, counterprotesters, who had shown out in large numbers, rallied and rejoiced. However, protesters with an anarchist group arrived at the park wearing masks and hoods that covered their faces.
Prime Minister Narendra Modi scrapped high value currency notes past year in a bid to fight corruption and wipe out black money. The domestic market was the prime source of new contract wins, while the trend in new export business also remained robust.
Eight candidates are in the fray but essentially the AAP , the BJP and the Congress are locked in a triangular contest. He defeated BJP's Ved Prakash by 24,052 votes while Congress' Sandeep Kumar secured third position.
The 30-year-old Upton is having a strong season for the struggling Tigers , batting.279 with 28 homers and 94 RBIs. The Angels are now only a game behind the Minnesota Twins for the second wild card spot in the American League.
Jacob Eason Leaves Game With Leg Injury
Coach Kirby Smart said this week he had no plan to create time for Fromm, adding " Jacob Eason is our quarterback". The Mountaineers also had a long evening trying to stop Georgia's tailback tandem of Nick Chubb and Sony Michel .
Humiliated for period stain, Indian girl kills herself - parents
He said Anitha had scored 196.5 cut-off marks and it would have gained her a seat in one of the best State-run medical colleges. Dejected after failing to secure an MBBS seat despite her efforts, Anitha committed suicide on Friday at her home in Ariyalur .
Chelsea agree Zappacosta deal
Chelsea left it late on deadline day to complete the signings of full-back Davide Zappacosta and midfielder Danny Drinkwater . Meanwhile, BT Sport pundit James Horncastle says the signing of the 25-year-old seems like a panic buy by the London club.
Mosquitoes in Redding test positive for West Nile virus
Those pesky mosquitoes that torment your summer mornings and evenings may be more of a concern than an itchy bite. Those who do usually experience mild symptoms, such as a fever, headache, muscle aches, rash and fatigue.
Dhaka delight as Bangladesh Tigers maul Australia
The opener scored 112 runs but didn't get any support from the middle-order as the second highest score came for Steve Smith (37). It's often said that the biggest weapon of an athlete in his mind and Bangladesh proved exactly that.
Halo: 343 Industries Working with VR / AR for Future Titles
Note that they include a number of developers who already have published virtual reality apps, or just apps for Windows. This includes the recently revealed Dell Visor , which is priced at $400 and can offer support for full motion control.
President Trump to talk taxes in Springfield
The president framed the US tax code problem in terms of competitiveness. "I think Congress is going to make a comeback", he said. President Donald Trump will start his campaign to reform the nation's tax code Wednesday with a speech in Springfield, Mo.
ISIS leaves Lebanon-Syria border
Coalition aircraft struck a small bridge and cratered a road to hinder the convoy's progress. Iran has been one of Assad's main backers since Syria's conflict began in March 2011.
Parties push for more progress as Brexit talks resume
The EU wants to settle Britain's so-called Brexit divorce bill before talks begin on the new trade relationship with the UK. The UK isn't taking Brexit very seriously , according to European Commission president Jean-Claude Juncker .
Houston Police Officer Drowns in Harvey Flooding
Perez lost his life because he tried to make it happen, he tried to get at his post.that's the ultimate sacrifice", he said . At the news conference, Acevedo became choked up describing Perez as "one of the sweetest people I've ever met".