The US-Korea Institute at Johns Hopkins School of Advanced International Studies says new satellite imagery shows modifications underway at the west coast site of Sohae mean it could eventually accommodate rockets up to 50 metres long. The analysis was published today on the institute's website, 38 North.
North Korea is not thought to have such a large rocket, but in December 2012 it launched into space the 30-metre-long Unha-3. The US viewed that as a worrying sign of the North's development of ballistic missile technology.