PYONGYANG, March 15 (Xinhua) — Top leader of the Democratic People's Republic of Korea (DPRK) Kim Jong Un said the country will conduct a test of nuclear warhead and test-fire several different ballistic rockets capable of carrying nuclear warheads in a short time, the official KCNA news agency reported Tuesday.

Kim made the remarks when he guided an environmental simulation for re-entry into atmosphere of the warhead tip of a ballistic missile.

The simulation was conducted to "verify the thermodynamic structural stability of newly-developed heat-resisting materials under the high pressure and thermal flow caused by aerodynamic heating" when a ballistic rocket re-enters the atmosphere, the KCNA said, adding that the test results met all technical parameters.

Kim noted that by acquiring the re-entry technology, the DPRK has made great progress in ballistic rocket technology, which strengthens the country's defense capability and the munition industry.

When guiding a drill of ballistic rockets last week, the DPRK top leader underscored the need to step up efforts to develop nuclear weapons and diversify means for delivering nuclear warheads.

Kim said then that the DPRK has been able to produce miniaturized and standardized nuclear warheads for ballistic missiles, and that "can be called a true nuclear deterrent."