The United States has seen increased activity around a North Korea site suggesting movement of components and propellant to be able to conduct a space launch in the near future, a U.S. official told Reuters on Thursday.

"Our concern though is that they do a space-launch but really it's the same technology to develop ICBMs," the official said, referring to inter-continental ballistic missiles.

The official added such a launch could happen within a couple of weeks.

(Reporting by Phil Stewart; Editing by Susan Heavey)