NATO is effectively powerless to rein in North Korea's nuclear threat, according to a Brussels-based expert.

With international concern rising over Kim Jong Un's intentions, the terrifying truth about North Korea's nuclear threat is that it cannot be stopped by one system or even multiple systems.

That is the pessimistic prognosis of Fraser Cameron, director of the respected EU-Asia Centre.

North Korea is a tiny, poor, backward nation with limited missile capabilities and a small nuclear stockpile, but it poses a very serious threat to the US and its allies.

NATO, which has its headquarters in Brussels, and EU leaders have repeatedly issued a series of warnings in recent months about the nuclear tests and multiple ballistic missile launches conducted by North Korea in 2016.

The latest came on Dec. 12, 2016, with a statement saying the behavior "presents a serious threat to international peace and security."

In one of his many tweets, US President-elect Donald Trump on Jan. 2 said, "North Korea just stated that it is in the final stages of developing a nuclear weapon capable of reaching parts of the US," before adding, "It won't happen!"

But the assessment from Cameron, a recognized expert on the Korean Peninsula, is not what the Western alliance – already dismissed by Trump as "obsolete" – may wish to hear.

The truth, the analyst argues, is that North Korea, the only country to have tested nuclear weapons in the 21st century, has just as much of a say in whether its potential nuclear arms can or will reach the US or Europe as Trump and NATO do.

Cameron declares, "There is nothing NATO can do to change this."

North Korea's nuclear arsenal may still be in its early phases but Kim Jong Un, the country's leader, commands about 100 missile launchers with several missiles for each.

In comparison, the US has 1,796 nuclear missiles deployed, another 4,500 stockpiled, and 2,800 retired and waiting to be dismantled.

Ultimately, there is extremely little the United States, or NATO, can do to stop a rogue nation like the DPRK should it choose to strike, argues Cameron.

The Briton says, "There is a mountain of speculative literature on DPRK nuclear weapons, but the bottom lines is that no one knows how advanced they are; and there are no good options."

He added, "Remember both Bush and Obama came into office saying they would not allow DPRK to develop nukes.

"The problem is that Seoul is just 60 km from the border and would be obliterated in any conflict."

Cameron, whose think tank seeks to forge closer ties between the EU and Asia, adds, "Kim's top priority is survival and he looks around the world and sees that no nuclear-armed state has been attacked. But when you give up nuclear weapons as with, for example, Ukraine and Libya, you are attacked."

He goes on, "It is pretty obvious what line to take."

But, says Cameron, the North Korean leader also knows that any launch of a nuclear weapon would mean "instant incineration," adding, "This is not something he is likely to wish for."

He adds, "So unless China turns the energy screws we shall have to live with the status quo. NATO has no competence to deal with out-of-area threats such as DPRK. It monitors developments, but that is it.

"It is purely a US problem."

Paddy Ashdown, a former leader of the Liberal Democrats in the UK,  also agrees that China, rather than NATO, is the "key" to addressing the North Korean threat.

China has recently hit back at Donald Trump's claim that Beijing isn't doing enough to rein in North Korea, cautioning the US president-elect not to "escalate" an already tense situation. China is Pyongyang's only friendly nation of note and accounts for 90 percent of its trade. The continued existence of North Korea is of strategic advantage to Beijing if the alternative is a unified Korean Peninsula administered by Seoul, a staunch US ally.

Elmar Brok, a German centre right Member of the European Parliament, said, "The European Union strongly supports the work of all negotiating parties," and welcomed the resolution adopted by the UNSC condemning North Korea's 5th nuclear test.

"As already pointed out by the council in Dec. 2016, the European Union strongly condemns the nuclear tests and ballistic missile launches conducted by North Korea. These actions represent a serious threat to international peace and security and undermine the global non-proliferation regime which the EU has been a steadfast supporter for decades, Brok said. "I believe that especially the US and China must strengthen their efforts and take a joint stance towards North Korea. China should assume its responsibilities and fulfill its role as mediator."

Brok, who chairs the Parliament's influential Foreign Affairs Committee, added, "China should assume its responsibilities and fulfil its role as mediator."

Steven Pifer, a senior fellow at the Brookings Institution, cautions that NATO allies would oppose introducing a nuclear-armed air-to-surface missile. And, he points out, those allies that most likely would want to host such a weapon are in Central Europe, closer to Russia.

With tensions over Kim Jong Un showing no sign of abating, NATO Secretary-General Jens Stoltenberg has again "strongly" condemned the DPRK's nuclear testing, which the Norwegian official says "increases regional tensions and insecurity."

A NATO official added, "DPRK's proliferation activities regularly feature in declarations from high-level NATO meetings. On Dec. 15, 2016, the North Atlantic Council held a meeting focused on North Korea's actions and in particular its nuclear and missile programmes. At the meeting, NATO allies reaffirmed their support to relevant UN Security Council Resolutions, as they have done in the past.

"They reiterated their calls on Pyongyang to immediately cease and abandon all its existing nuclear and ballistic activities in a complete, verifiable and irreversible manner and re-engage in international talks; and to fully respect its international obligations and commitments."

This is echoed by the European Council, the body which represents EU member states, with a spokesman saying it was "concerned" by the DPRK's development of nuclear weapons, which is "bound to seriously aggravate the security situation in Asia and beyond."

The spokesman went on, "We call again on the DPRK to re-engage in a credible and meaningful dialogue with the international community."

Lukasz Kulesa, research director at the UK-based European Leadership Network (ELN), said, "NATO countries have been consistently condemning provocative actions by North Korea, including ballistic missile launches and nuclear tests. They have also supported introduction of sanctions, and are analyzing the developments in the region. At the same time, defense against the DPRK is certainly not the focus of NATO's plans and activities.

"If US (or Canada's) mainland territory is attacked by North Korea at some point in the future, that would be the case for Article 5 invocation. However, it is unlikely that in such case the US would seek military assistance from its European allies before retaliating - therefore it would make little sense for NATO to use up its resources for planning for such contingency."