Results of the US review of options to deal with North Korea will come out "sooner than later," a senior White House official said Tuesday.

Christopher Ford, senior director for weapons of mass destruction and counterproliferation on the White House National Security Council, made the remark during a nuclear policy discussion, saying the North Korea problem "clearly needs a new look."

"Past approaches to trying to contain that threat haven't worked as well as one would have liked them to work. So, you won't be surprised to learn that North Korea policy is, of course, subject to a broad review that does very explicitly look at the whole spectrum of possibilities," Ford said during the discussion organized by the Carnegie Endowment for International Peace.

"Don't have answers on what will come out of that review but you may see something sooner rather than later on that," he said.

"The NSC's Asia Director was one of the first out of the box in policy review terms and starting to work on North Korea review through the interagencies."

Ford also stressed the seriousness of the North Korean threat.

"It's got an unchecked nuclear weapons program, an accelerating missile-testing program that is increasingly poised to deliver a nuclear weapon over intercontinental ranges to the US It clearly presents a threat that we can't ignore," he said.

The official reacted negatively to calls in South Korea for nuclear armament, saying the long-standing US objective has been to make sure "those questions never need to arise on their own merits and to make sure that the circumstances that might drive that kind of consideration don't come about."

Earlier, White House press secretary Sean Spicer said that the US in coordination with allies "is exploring a new range of diplomatic, security and economic measures in response to the grave and escalating threat posed by North Korea's nuclear and ballistic missile programs."

No details were given as to what those measures will look like, but the new package of options is expected to center on ramping up pressure on Pyongyang, rather than reopening negotiations.

Secretary of State Rex Tillerson said during a trip to South Korea and Japan last week that two decades of diplomatic efforts to disarm the North have failed, and there was no point in pursuing the diplomatic path any longer. He also said that the US was considering a wide range of options, including the use of military force.

In response, the North said it is fully ready for "any war" with the US.

On Monday, US President Donald Trump called the North Korean situation "disgraceful," arguing that he's inherited a lot of problems from the previous administration.

"The fact is we inherited a mess. It's a mess," Trump said in an address in Kentucky, picking the Middle East and North Korea as examples of such problems. "North Korea, I'll tell you what, what's happening there is disgraceful and not smart, not smart at all. So many different problems."

It was the latest in a series of remarks Trump has made about the North in recent days.

On Friday, Trump tweeted, "North Korea is behaving very badly. They have been 'playing' the United States for years. China has done little to help!" He also said on Sunday that North Korean leader Kim Jong-un is acting "very, very badly."

That appears to show the problem weighs on Trump's mind.

Former President Barack Obama reportedly warned Trump that North Korea will be one of Trump's biggest foreign policy problems when they met at the White House after Trump's election. (Yonhap)