North Korea has successfully refloated a new destroyer that capsized upon launch last month, with state media reporting the damaged vessel will be moved to a dry dock in a different shipyard for repairs.

North Korea says it righted a capsized destroyer and moored it at a pier in the northeastern port of Chongjin as it continues to repair a new warship leader Kim Jong Un has described as a significant asset for his nuclear-armed military.

North Korea has launched a warship two weeks after it was damaged during an earlier launch attempt, in an incident that drew harsh criticism from the country's leader Kim Jong Un. The 5,000-tonne destroyer, which was restored to balance earlier this week, was launched on Thursday and is now moored at a pier, state-run news agency KCNA said.