U.S. investment bank Goldman Sachs says a unified Korea could surpass France, Germany or Japan in terms of growth domestic product, in 30 to 40 years.

Goldman Sachs presented the projection in a recent report, saying despite North Korea's economy being on the brink of collapse, it offers a large and cheap labor force and abundant minerals that the South currently depends on from overseas.

The report also said the cost of reunification could be affordable on the back of appropriate government policies and by following China and Hong Kong's reunification model, which allows two political and economic systems to co-exist.