PYONGYANG - Top leader of the Democratic People's Republic of Korea (DPRK) Kim Jong Un has overseen a successful test of the heavy-lift engine of a new-type intercontinental ballistic rocket, the official KCNA news agency reported Saturday.

The ground test conducted at the Sohae Space Center proved a great success, the KCNA said, without specifying when the test was carried out.

The success was of significance in strengthening nuclear force in quality in national defense science and technology, it said, adding that the engine of the intercontinental ballistic rocket met all scientific and technological indexes.

Kim made the order the start the test and he was satisfied with the test result, the report said.

The DPRK was now able to tip the new-type intercontinental ballistic rockets with nuclear warheads and put the U.S. mainland within their striking range, he said.