North Korea: UN has 'exhausted' its options and America may hand issue to Pentagon, Nikki Haley says

US ambassador to the United Nations Nikki Haley says the UN Security Council has run out of options to contain North Korea's nuclear program, adding Washington may have to turn the matter over to the Pentagon.

Key points:

• Ms Haley says if North Korea continues it "will be destroyed"
• Donald Trump calls Kim Jong-un "rocket man" and praises sanctions effects
• Security adviser HR McMaster says preparing a military option is becoming necessary

"We have pretty much exhausted all the things that we can do at the Security Council at this point," Ms Haley told CNN, adding that she was perfectly happy to hand the North Korea problem over to Defence Secretary James Mattis.

As world leaders head to the United Nations headquarters in New York for the annual General Assembly meeting this week, Ms Haley's comments indicated the United States was not backing down from its threat of military action against North Korea.

On Thursday, North Korea launched a missile over Japan into the Pacific Ocean in defiance of new UN Security Council sanctions banning its textile exports and capping imports of crude oil.

China has urged the United States to refrain from making threats to North Korea, but when asked about President Donald Trump's warning last month that the North Korean threat to the United States will be met with "fire and fury", Ms Haley said "it was not an empty threat".

"If North Korea keeps on with this reckless behaviour, if the United States has to defend itself or defend its allies in any way, North Korea will be destroyed," she said.

"And we all know that. And none of us want that. None of us want war.

"We're trying every other possibility that we have, but there's a whole lot of military options on the table."

 Pyongyang has launched dozens of missiles as it accelerates a weapons program designed to provide the ability to target the United States with a powerful, nuclear-tipped missile.

On Saturday, North Korea warned that it was nearing its goal of reaching "equilibrium" in military force with the United States.

President Trump is reportedly planning to meet with South Korean President Moon Jae-in on the sidelines of the UN General Assembly.

On Sunday, Mr Trump took to Twitte

r to asked how "rocket man" was doing, presumably referring to Kim Jong-un's increasing missile launches.

"I spoke with President Moon of South Korea last night. Asked him how Rocket Man is doing. Long gas lines forming in North Korea. Too bad!"