North Korea failed to meet its previous five-year economic goals due to its dependence on heavy industries amid crippling sanctions, a researcher at a state-run think tank said Wednesday.

Kim Seok-jin, a researcher at the state-run Korea Institute for National Unification (KINU), cited the North's investment strategies in rebuilding the heavy industries and the following chronic power shortage as the main reasons for its failure in achieving the five-year economic goal.

In 2016, North Korea put forward its five-year economic scheme at the party congress, with priorities focused on developing the mining and heavy industries, including chemicals and metals.

Investing in such industries are ineffective as they show low productivity compared with the cost while consuming an enormous amount of electricity, the expert said.

"The biggest problem with the outdated strategy was that it led to chronic power shortages," he said.

At the eighth congress of the ruling Workers' Party last month, Kim admitted the failure to meet the country's previous five-year development goals and put forward a new five-year plan focusing on self-reliance.

During the session, Kim also said the North will focus its investment on the metal and chemical industries.

The expert said the North's continued investment in such industries and global sanctions are likely to keep dragging down the economy.

"The North's economic crisis will continue unless it comes up with completely new development strategies, including on denuclearization and opening up the country," the expert said. (Yonhap)