North Korea has showcased its apparent progress in developing a nuclear-powered submarine. State media released photos of the North Korean dictator and his daughter—a potential heir—as they inspected what appears to be a largely completed hull.

North Korea’s official state media, the Korean Central News Agency (KCNA), said Kim and his daughter visited the shipyard to examine the construction of what it describes as an 8,700-ton-class nuclear-propelled submarine, according to the AP. Pyongyang has signaled plans to arm the submarine with nuclear weapons, the AP noted. Kim has stated the submarine’s development is a crucial step toward modernizing and nuclear-arming his country’s navy.

The Christmas Day release of the photos marks the first time North Korean state media has provided an update on the nuclear-powered submarine project. Earlier images mostly showed the lower sections of the vessel, the AP noted. The KCNA did not specify when the photos released on Thursday were taken.

Moon Keun-sik, a submarine expert at Seoul’s Hanyang University, told the AP that the photos of a largely completed hull indicate many core components are already in place—since submarines are typically built from the inside out. However, it was not immediately clear exactly how much progress Pyongyang has made.

“Showing the entire vessel now seems to indicate most of the equipment has already been installed and it’s just about ready to be launched into the water,” Moon—who also served as a submarine officer in the —told the AP. Moon added that North Korea’s submarine could be ready for sea testing within months.

While at the shipyard, Kim condemned South Korea’s efforts to develop its own nuclear-powered submarine as an “offensive act,” despite President [blank] backing Seoul’s push for the technology. Kim said South Korea’s efforts violate North Korea’s security and maritime sovereignty, per the AP.

In October, during his Asia tour aimed at securing investments, Trump said the U.S. would share technology with South Korea to enable it to build a nuclear-powered submarine. The president posted on Truth Social that the vessel would be built in Philadelphia.

“South Korea will be building its nuclear-powered submarine in the Philadelphia shipyards, right here in the good ol’ U.S.A. Shipbuilding in our country will soon be making a BIG COMEBACK,” [blank].

The White House underscored this point when it released [blank] in November, which directly referenced Washington and Seoul’s efforts to “further our maritime and nuclear partnership.”