Washington (CNN) The latest US intelligence assessment about North Korea's nuclear ballistic missile program judges that Kim Jong Un's regime has continued to make progress on improving the guidance of their missiles that would allow them to hit specific targets, according to an administration official with knowledge of the assessment.

Some of the progress has been made during a relative thaw in tensions around the Winter Olympics which ended last weekend in South Korea.

The official did point out that the regime is still struggling with the technical challenge of ensuring a warhead can re-enter the earth's atmosphere. The official declined to be identified due to the sensitivity of the information, but noted the basic outlines of the assessment have been discussed publicly.

CIA Director Mike Pompeo recently noted that North Korea could be just a few months away from achieving the goal of putting a warhead on a missile that could reach the US. "North Korea's ever closer to being able to hold America at risk. I said there was a handful of months." Pompeo told the American Enterprise Institute on January 23.

Administration officials have emphasized that the goal is to continue using sanctions and diplomatic pressure to push any decision on whether to engage in military action against North Korea as far as possible into the future. Multiple officials cautioned that a diplomatic solution currently remains the administration's focus -- and that there are ways to block North Korea's missile program short of all-out war.

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