North Korea announced on Friday (September 8th) that it had built a “tactical nuclear attack submarine” as part of its efforts to boost its naval strength, state news agency KCNA reported. The new submarine was unveiled Wednesday at a ceremony presided over by North Korean leader Kim Jong-un, who said the craft is part of the Navy’s “progress in nuclear weaponry in the future,” according to KCNA.

The launch of the submarine, named Hero Kim Kun Ok, “marked a new chapter in strengthening the DPRK’s naval forces,” according to the state agency, which refers to the abbreviation of Korea’s official name North. During the ceremony with confetti and balloons, Kim Jong-un spoke of the “strategic and tactical plan to continuously strengthen the modernity of the submarine and surface forces and the advancement of the Navy’s nuclear armament in the future “, according to KCNA.

He further emphasized that “arming the navy with nuclear weapons is becoming an urgent task,” according to KCNA. On Thursday, Kim Jong-un inspected the submarine as it prepared to conduct a test trip.