Satellite photos show that North Korea is building a submarine with ballistic missiles and may be preparing to test a submarine missile, according to experts at a Washington-based think tank, according to an analysis of commercial images.
Monday's photos of Sinpo South Shipyard appear to endorse North Korean state media reports of a "newly built submarine," which was inspected by the country's leader, Kim Jong Un, in July, said Joseph Bermudez and Victor Cha of Beyond Parallel, a funded research project by the Center for Strategic and International Studies (CSIS).
The photos show aid ships and a crane that, similar to the past, could be used to haul a bark for a submarine missile test at sea, the analysts said in a written report.
However, the two analysts said it was unclear when a test could be performed inty.
Although media reports from North Korea claim that the deployment of the new submarine is imminent, analysts say it is more appropriate to describe the ballistic missile submarine threat as "more likely than imminent." ,
Even after construction, it would take a year or more to test and get the submarine operational, Bermudez and Cha said.
However, continuing local activity in the last three years indicates that North Korea is approaching securing a capability that provides the regime with an alternative means of delivering nuclear weapons and that is more difficult for the United States and its allies follow.
"The construction and commissioning of a true ballistic missile submarine (SSB) would represent a significant advance in the North Korean ballistic missile and nuclear threat and complicate the defense given the difficulty of pursuing and / or targeting such capabilities, the analysts in the region have had good experiences.
The latest images suggest that North Korea is making real progress in developing a second leg of the nuclear triad. They are approaching a viable nuclear force, "the analysts said.
The construction of a submarine-based nuclear force would also lessening "prospects for complete denuclearization," the report said: "Donald Trump has held two summits with Kim Jong Un to persuade the regime to abandon rockets and nuclear weapons to ease economic sanctions, but so far North Korea has refused. In recent months, North Korea has conducted numerous short-range missile tests.
North Korea has warned Washington that it could abolish nuclear talks and resume nuclear and long-range missiles when testing joint military exercises with South Korea.The regime has not had a long-range rocket test since 2017 more performed.  Pyongyang announced in 2016 that it has tested its first submarine-launched ballistic missile. The solid rocket was designed to be transported by the country's only Sinpo-class submarine, which has only one rocket tube. Military analysts have speculated that North Korea might try to build a multi-tube submarine.
Satellite images of the Sinpo South Shipyard and surrounding area since 2015 have not yet provided conclusive evidence for the construction of a new submarine with ballistic missiles. But Bermudez and Cha said on Tuesday that there was "substantial circumstantial evidence," including a new on-site infrastructure capable of supporting such a project, improvements in shipyard construction capacity, and transportation of parts inside and outside the site. The Sinpo South Shipyard is one of the few North Korean yards on which submarines can be built, and submarines have already been built.
Last year, 15 cranes were installed along the shipyard dock. Other North Korean submarine bases and bases have used similar cranes to suspend the network via submarines to prevent overhead observers.