North Korea has tested a high-thrust solid-fuel engine that experts said would allow quicker and more mobile launch of ballistic missiles, as it seeks to develop a new strategic weapon and speeds up its nuclear and missile programs.

The test, overseen by leader Kim Jong Un, was conducted on Thursday at North Korea's Sohae Satellite Launching Ground that has been used to test missile technologies, including rocket engines and space launch vehicles, the official KCNA news agency reported on Friday.

Experts say the test appears aimed at developing a new solid-fuel intercontinental ballistic missile (ICBM) given the thrust of the engine, which the North said was "the first of its kind" in the country.