Kim Jong Un, top leader of the Democratic People's Republic of Korea (DPRK), has inspected a solid-fuel rocket engines and rocket warhead tips, including those for intercontinental ballistic missiles (ICBM), design and producing institute dedicated to the country's missile program, said official media Wednesday.

The Korean Central News Agency said Kim gave field guidance to the Chemical Material Institute of the Academy of Defense Science without specifying the date of the inspection.

Usually news about the top leader is reported one day after it takes place by DPRK official media.

"He noted that in recent years the institute has a lot of jobs in a patriotic drive for breaking through the cutting edge true to the Workers' Party of Korea's policy of attaching importance to the defense science and technology and policy of the munitions industry," said the report.

Kim also learned about the processes for manufacturing ICBM warhead tip and solid-fuel rocket engine and made a field survey of the process for manufacturing solid-fuel rocket engine and specified tasks and ways for normalizing the production at a higher level, said the report.

"He instructed the institute to produce more solid-fuel rocket engines and rocket warhead tips by further expanding engine production process and the production capacity of rocket warhead tips and engine jets by carbon/carbon compound material," said the report.

The DPRK has a large coal mining industry which produces carbon and carbon compound material whose advanced products are believed to be capable of replacing heavy oil fuels used for launching rockets and missiles by other countries.

The DPRK conducted two ICBM test firings last month which its says will be self-defense deterrence against the United States.