The analysis published yesterday comes just three weeks after North Korea drew international condemnation for conducted its fourth nuclear test explosion.
The official told The Associated Press the US has seen activity at a ballistic missile test site that is consistent with previous tests, but the official would not go into more detail.
The official was not authorised to speak publicly on the matter and requested anonymity.
The North Korea-focused website, 38 North, said it has detected what could be the early stages of preparation for launching a space launch vehicle at the nation's main rocket launch site at Sohae. It based its findings on satellite imagery taken this week.
More From This Section
The UN Security Council is deliberating over how to respond to the January 6 underground nuclear explosion. The US is pressing for tighter sanctions a step that China, the North's only ally, appears reluctant to take.
Governments and experts have been skeptical about North Korea's claim it tested a hydrogen bomb, but whatever device the North detonated, it will likely push the country a step closer toward its goal of manufacturing a miniaturized warhead to place on a missile that can threaten the US mainland. A major launch would only deepen those concerns.
The 38 North analysis said a rocket test in the coming week appeared unlikely. Imagery from Monday showed vehicles or equipment and personnel near the rocket launch tower, but a rocket wasn't visible. The website said there's a high level of uncertainty about what snapshots of activity at the launch pad offered by the commercial imagery indicate.