Explainer: What is happening between the US and North Korea?
Defiant Donald Trump has warned Kim Jong Un's government to "get their act together" or face extraordinary trouble - suggesting he had been too mild when he vowed to unleash "fire and fury" on North Korea if it continued to threaten the US.
"Maybe that statement wasn't tough enough," the US president said, firing the latest salvo in the escalating exchange of threats between the nuclear-armed nations.
There was no obvious march towards combat, a day after North Korea laid out plans to strike near the US island territory and major military hub of Guam, despite the angry rhetoric from both sides, but the stage is set for new confrontation.
But how did this dispute start?
Here's all you need to know about the current tensions between the US and North Korea.
When did this begin?
Donald Trump first became irate with North Korea when Otto Warmbier, the 22-year-old American student who was detained in North Korea in 2016, died just six days after he was returned to the United States.
He had been arrested for trying to steal a propaganda poster, he returned to the US in a coma in June.
His family declined to confirm his cause of death but said he had been subjected to "awful, torturous mistreatment."
President Donald Trump called North Korea a "brutal regime" after the death was announced.
What happened next?
Though tensions have been building for months amid new missile tests by the North, the pace has intensified since Saturday, when the United Nations Security Council passed sweeping new sanctions Mr Trump had requested.
Following reports that US intelligence suggests the North might be able to pair a nuclear warhead with a missile capable of reaching targets on the United States mainland, Mr Trump warned North Korea that "it faces retaliation with fire and fury unlike any the world has seen before".
He also said he would soon announce a request for a budget increase of "billions of dollars" for anti-missile systems.
How did Kim Jong Un's government react?
A general who heads North Korea's rocket command, warned Pyongyang was preparing a plan to fire four of its Hwasong-12 missiles over Japan and into waters around Guam, the tiny US Pacific territory island which hosts 7,000 military personnel on two main bases and has a population of 160,000.
It said the plan could be finalised within a week or so and would then go to leader Kim Jong Un for approval.
What do US officials think?
Current and former US officials said if war did come, America and its allies would be likely to hit hard and fast, using air strikes, drone operations and cyber attacks aimed at military bases, missile sites, artillery, communications, command and control headquarters and intelligence gathering and surveillance capabilities.
US defence secretary Jim Mattis said on Thursday that while it was his responsibility to have military options, the US effort was focused on diplomacy and the Trump administration was working with its allies on a diplomatic solution.
US secretary of state Rex Tillerson sought to calm the sense of crisis, saying: ""Americans should sleep well at night."
What is the next move for the US?
The US and South Korean military plans to move ahead with large-scale exercises later this month that North Korea, now finalising plans to launch missiles towards Guam, claims are a rehearsal for war.