There have been reports of Iran allying with North Korea to build nuclear weapons for years, going back to the 1990s.  From what we know, both Pakistan and North Korea provided hardware to Iran in their initial efforts to build a nuclear program.  North Korean scientists were said to have been in Iran as late as 2005.

Now comes word that North Korea may be harboring an Iranian nuclear bomb facility.  If true, it would make any deal with Iran an exercise in futility – which is probably why the White House isn't saying anything about it.

Daily Beast:

But no inspections of Iranian sites will solve a fundamental issue: As can be seen from the North Korean base housing Tehran’s weapons specialists, Iran is only one part of a nuclear weapons effort spanning the Asian continent. North Korea, now the world’s proliferation superstar, is a participant. China, once the mastermind, may still be a co-conspirator. Inspections inside the borders of Iran, therefore, will not give the international community the assurance it needs.

The cross-border nuclear trade is substantial enough to be called a “program.” Larry Niksch of the Center for Strategic and International Studies in Washington, D.C., estimates that the North’s proceeds from this trade with Iran are “between $1.5 billion and $2.0 billion annually.” A portion of this amount is related to missiles and miscellaneous items, the rest derived from building Tehran’s nuclear capabilities.

Iran has bought a lot with its money. Mohsen Fakhrizadeh, thought to be Tehran’s chief nuclear scientist, was almost certainly in North Korea at Punggye-ri in February 2013 to witness Pyongyang’s third atomic test. Reports put Iranian technicians on hand at the site for the first two detonations as well.

The North Koreans have also sold Iran material for bomb cores, perhaps even weapons-grade uranium. The Telegraph reported that in 2002 a barrel of North Korean uranium cracked open and contaminated the tarmac of the new Tehran airport.

In addition, the Kim Jong Un  regime appears to have helped the Islamic Republic on its other pathway to the bomb. In 2013, Meir Dagan, a former Mossad director, charged the North with providing assistance to Iran’s plutonium reactor.

[...]

Even if Iran today were to agree to adhere to the Additional Protocol, it could still continue developing its bomb in North Korea, conducting research there or buying North Korean technology and plans. And as North Korean centrifuges spin in both known and hidden locations, the Kim regime will have a bigger stock of uranium to sell to the Iranians for their warheads. With the removal of sanctions, as the P5+1 is contemplating, Iran will have the cash to accelerate the building of its nuclear arsenal.

So while the international community inspects Iranian facilities pursuant to a framework deal, the Iranians could be busy assembling the components for a bomb elsewhere. In other words, they will be one day away from a bomb—the flight time from Pyongyang to Tehran—not one year as American and other policymakers hope.

What makes this story ring true is North Korea's desperation for hard currency.  It can't feed its army, much less the civilian population, wihout purchasing food abroad.  A couple of billion dollars from Tehran, not to mention what highly enriched uranium is going for these days and the sale of other components for a bomb, could give the North a steady inflow of cash they desperately need.

The respected foreign affairs site The Diplomat casts doubt on this scenario.  They quote from a Congressional Research Service study that largely debunks the Iran-North Korea nuclear cooperation theory.  Still, the secretive nature of North Korea, and Iran's willingness to work with Sunni terrorist groups like al-Qaeda and Hamas, shows that the Iranians can put cultural, religous, and ideological differrences aside to achieve their ultimate goals.