North Korea has successfully tested new solid-fuel engines for intermediate-range ballistic missiles (IRBM), state-run media said Wednesday, in the nuclear-armed country’s latest development of a weapon capable of stealthily striking Japan.

"At a time when the dynamic struggle is being accelerated to bolster up the country's defense capabilities in every way, the missile industry of the DPRK has developed new-type high-thrust solid-fuel engines for intermediate-range ballistic missile again, which are of important strategic significance,” the North’s official Korean Central News Agency reported.

It said the country had “successfully conducted the first ground jet tests of the first-stage engine and the second-stage engine” on Saturday and Tuesday, respectively.