North Korea has highlighted its growing “military muscle” with the launch of a "new type” of submarine-launched ballistic missile (SLBM), the nuclear-armed country said Wednesday, in a move that has intensified talk in Tokyo of Japan acquiring the capability to strike enemy bases.

The North’s official Korean Central News Agency said in a dispatch that the new weapon “will greatly contribute to putting the defense technology of the country on a high level and to enhancing the underwater operational capability” of its navy.

In an apparent sign that the North hopes to regularize these kinds of tests, leader Kim Jong Un did not oversee the launch, instead delegating the duties to a lower-level official, KCNA said.