Defense Secretary Jim Mattis says the Trump administration is working with its allies on a diplomatic solution to escalating tensions with North Korea.
Speaking with reporters in Mountain View, California, Mattis says his responsibility is to have military options but the American effort is focused on diplomacy.
He points out the U.N. Security Council unanimously voted last week to characterize North Korea's statements as a "threat to the world's community."
He asks, "How often do you see France, China, Russia, the U.S. voting unanimously on any issue?"
Mattis says the tragedy of war is well known and "it doesn't need another characterization beyond the fact that it would be catastrophic."
Australia's prime minister says his country would come to the aid of the United States if North Korea attacks Guam.
Prime Minister Malcolm Turnbull told Melbourne Radio 3AW: "We would come to the aid of the United States. How that manifests itself will obviously depend on the circumstances and consultations with our allies."
Turnbull added: "If North Korea decides to carry out some of its violent threats, then obviously terrible consequences will follow."
The prime minister says he discussed the threat with U.S. Vice President Mike Pence overnight.
Turnbull says: "The United States knows as we know and as Donald Trump reaffirmed ... that America stands by its allies including Australia of course and we stand with the United States."
He added: "It is absolutely rock solid and everyone understands that. In terms of defense, we are joined at the hip."
The United Nations says Secretary-General Antonio Guterres is "troubled" by the escalating rhetoric from all sides in the North Korea nuclear dispute.
U.N. spokesman Stephane Dujarric says Guterres "welcomes all initiatives that will help de-escalate the tensions and a return to diplomacy."
Asked Thursday whether the secretary-general could be a mediator, Dujarric says, "He is always willing to do so."
The U.N. in the past has had an envoy for North Korea, but Dujarric says "every situation is different and it's important not to make empty gestures."
Dujarric says Guterres welcomed the U.N. Security Council's adoption last Saturday of a resolution imposing new sanctions on North Korea, including banning any coal, iron lead and seafood exports, and is urging all U.N. member states to implement it.
President Donald Trump says he's planning to add billions of dollars to the nation's anti-missile programs.
Trump tells reporters after a security briefing at his golf club in Bedminster, New Jersey, "We are going to be increasing our budget by many billions of dollars."
He says an announcement is planned soon.
Trump also says the nation's nuclear arsenal is in "in tip-top shape" and getting stronger. And he insists his administration has "done a lot of modernization" and "a lot of renovation" already.
Trump is also warning about the dangers of nuclear weapons, saying he'd like to "de-nuke the world." But he says that, until that happens, the U.S. "will be the most powerful nuclear nation on earth, by far."
President Donald Trump says that perhaps his 'fire and fury' warning to North Korea "wasn't tough enough." Trump is issuing a new warning over the North's development of nuclear weapons.
Trump says North Korea "better get their act together or they are going to be in trouble like few nations have ever been in trouble."
The president was addressing reporters during his vacation at his New Jersey golf club before a security briefing with top advisers.
It's the latest warning since he said earlier this week that North Korea faces "retaliation with fire and fury unlike any the world has seen before."
North Korea has said it may attack Guam in retaliation.
North Korea has announced a detailed plan to launch a salvo of ballistic missiles toward the U.S. Pacific territory of Guam, a major military hub and home to U.S. bombers, a move that if carried out would be its most provocative missile launch to date.
The announcement Thursday warned that the North is preparing a plan to fire four of its Hwasong-12 missiles over Japan and into waters around the tiny island, which hosts 7,000 U.S. military personnel on two main bases and has a population of 160,000.
Japan and South Korea vowed a strong reaction if the North were to go through with the plan.
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