WASHINGTON -- North Korea is only a "handful of months" away from being able to strike the mainland United States with a nuclear weapon, and Washington is working to extend that timeline, the head of the Central Intelligence Agency has said.

The assessment by Mike Pompeo, director of the CIA, comes after North Korea tested three intercontinental ballistic missiles and a sixth nuclear weapon last year. 

In an interview with CBS aired Monday, Pompeo was asked if the US saw the nuclear test coming.

"Yes. Here's what we can say," the American spy chief said. "We can always identify that the program is continuing. We'll never know the exact nature of what's taking place. We'll never know the exact moment that they're going to continue. But the core risk that the policymakers needed to know was that North Korea's nuclear weapons program is continuing to expand, advance, become more powerful, more capable, more reliable."

Those developments were shared with policymakers, he added.

Asked how close North Korea is to being able to carry out a nuclear attack on the mainland US, Pompeo replied, "A handful of months."

Acknowledging that he had made the same assessment more than six months ago, he added, "I hope to be able to say it a year from now as well. The United States government is working diligently to extend that timeline."(Yonhap)