North Korea claims to have carried out a "very important test" at its long-range rocket launch site.
The nation reportedly rebuilt the site after having partially dismantled it at the start of denuclearisation talks with the United States last year.
North Korea previously said its resumption of nuclear and long-range missile tests depends on the United States, amid dimming prospects their talks will resume.
Saturday's test at the Sohae Satellite Launching Ground will have "an important effect on changing the strategic position of (North Korea) once again in the near future", according to an unidentified spokesman from the North's Academy of National Defense Science.
Information was released in a statement carried by the country's official Korean Central News Agency.
North Korea did not say what the test included. Kim Dong-yub, an analyst at Seoul's Institute for Far Eastern Studies, said that North Korea likely tested for the first time a solid-fuel engine for an intercontinental ballistic missile.
The use of solid fuel increases a weapon's mobility and reduces the amount of launch preparation time.
CNN reported Friday a new satellite image indicated North Korea may be preparing to resume testing engines used to power satellite launchers and intercontinental ballistic missiles at the site.
Seoul's Defense Ministry said in a brief statement later Sunday that South Korea and the United States are closely monitoring activities at the Sohae site and other key North Korean areas.
Reporting by agencies.
