Severe power shortages have driven North Korea into a protracted economic slump for the past decade amid the reclusive country's focus on building up its nuclear weapons program, a state-run think tank said Sunday.

"North Korea's decadeslong economic slump is apparently due to the regime's inefficiency and military tensions stemming from Pyongyang's nuclear ambitions," the Korea Development Institute said in its latest report. "But power shortages are the main cause of the economic recession."

North Korea has been suffering from power shortages since the late 1970s, although the North Korean government has made constant efforts to tackle the power deficiency issue.

The country's electricity supply is equivalent to 4.3 percent of that of South Korea as of 2013.

The KDI report said that the power shortage dealt a heavy blow to North Korea's economy, which highly depended on the heavy and chemical industries. It said a lack of energy caused a slump in the mining sector, which again resulted in deepening power shortfalls. The country depends heavily on fossil fuel to generate power.

"We have to look more into North Korea's electricity industry as part of efforts to reduce reunification costs," the KDI report said, adding it is necessary to map out a detailed plan to deal with North Korea's power shortage. (Yonhap)