The building work at the Sohae satellite launch station has taken place roughly 50 metres from the launch pad, stoking fears of further missile activity in the area.
The site, which has previously been used for alleged missile testing, is reportedly being bolstered with more working spaces for Kim’s military henchmen.
Analysis from North Korea experts 38 North said: “At present, the structure has a footprint of approximately 1,100 square meters.
“Floor space, however, will depend on whether a finished basement or second floor is added.
“While it is too early to determine the purpose of this new structure, its close proximity to the launch pad strongly suggests that it is related to launch operations support.”
The site has been used for launches since 2012, and was the base of a successful launch of a long range rocket in 2016.
However while the North Korea regime claim they were attempting to catapult a satellite into space, officials worldwide have warned the real motive was to test long rang ballistic missile technology.
This launch of the Kwangmyongsong-4 satellite was one of the launches that pushed the US and South Korea into deploying the THAAD missile defence system nearby as a defence measure.
It comes as North Korea warns the United States it will turn to all-out war as it claims Donald Trump is undermining work towards preserving peace and security with South Korea.
The secretive state unleashed its fury against Mr Trump as officials blamed the US for past tensions on the Korean peninsula.
A warning, pumped out by the communist state’s propaganda machine, said outsiders would “never break the will of our nation to advance along the road of reunification, peace and prosperity”.
Pyongyang’s mouthpiece, the Korean Central News Agency (KCNA), said: “The US and other outsiders responsible for the division of the Korean nation are displeased with the improvement of the inter-Korean relations, making desperate efforts to turn the peaceful atmosphere on the Korean Peninsula back to confrontation and war.
“To improve the North-South relations and ensure durable peace on the Korean Peninsula is an urgent demand of our nation and an indispensable prerequisite to national reunification.
“The DPRK has always worked hard to this end and preserved peace and security on this land by smashing every reckless nuclear war move of the US with strong war deterrence.”