North Korea announced the successful ground test of a new type of "high-power engine," ostensibly for launching satellites, state media reported Tuesday, an advance that could bolster the isolated nation's burgeoning missile program.

Leader Kim Jong Un, who oversaw the event, urged scientists and technicians to make preparations for launching a satellite "as soon as possible on the basis of the successful test," the official Korean Central News Agency reported, a possible indication that the North may conduct a prohibited long-range rocket launch soon.

Observers have speculated that Pyongyang may mark the Oct. 10 founding anniversary of the Workers' Party of Korea by launching a missile or satellite.