Story highlights Pyongyang called the test a "great leap forward" for its rocket program

A major US effort is underway to monitor North Korea mobile missile launchers

Washington (CNN) Two US defense officials told CNN Monday that the rocket engine North Korea tested Sunday could possibly be used in an eventual intercontinental ballistic missile.

The officials added that it is still not clear whether the engine would require some adjustment to be used in an ICBM, if it can indeed be used that way at all, noting that the Pentagon is still analyzing the test.

Possession of an intercontinental ballistic missile could allow North Korea to threaten the continental United States. ICBM technology is considered difficult to develop, with advanced rocket design being a necessary step.

The engine had been camouflaged under netting prior to the test. There is a major effort underway to keep track of North Korean mobile launchers.

Pyongyang called the test a "great leap forward" for its rocket program after what it termed a successful testing of a new high-thrust engine, state media reported Sunday.

Read More