North Korea has developed the ability to miniaturize nuclear warheads and launch them at the US, the general in charge of the North American Aerospace Defense Command (Norad) said at a Pentagon news conference on Tuesday.

Adm. Bill Gortney told reporters that, according to the Pentagon's assessment, North Korea now has the capability to place miniaturized nuclear warheads on its latest KN-08 intercontinental ballistic missile (ICBM).

Pyongyang has "the ability to put a nuclear weapon on a KN-08 and shoot it at the homeland," Gortney said.

This union of highly advanced military capabilities places an additional strain on US missile defense. The KN-08 is a road-mobile ICBM, meaning Pyongyang can move the launch system throughout the country.

"It's the relocatable target set that really impedes our ability to find, fix, and finish the threat," Gortney said. "And as the targets move around and we if don't have the persistent stare and persistent [intelligence, surveillance, and reconnaissance] that we do not have over North Korea at this time, that relocatable nature makes it very difficult for us to counter it."

North Korea experts John Schilling and Henry Kan estimate that the KN-08 would have a maximum range of 5,600 miles, making the missile capable of hitting the West Coast of the continental US. The weapon, however, is unlikely to have the accuracy required for precision targeting on large US cities.

The missile also has yet to be flight-tested, raising questions, most prominently from South Korea's Ministry of Defense, as to whether the missile can even be outfitted with a nuclear warhead.

Gortney, however, said the Pentagon continued to believe that Pyongyang had a miniaturized nuclear weapon and a delivery system capable of reaching the US.

Gortney did qualify his statement by noting that it was better to be prepared for a North Korean nuclear capability even if there is uncertainty as to the actual state of the country's technology. And he believes the US could easily deflect a North Korean nuclear strike.

"Should one get airborne and come at us, I'm confident we would be able to knock it down," Gortney told reporters.

You can view Gortney's testimony below:

H/t The Lowy Institute