North Korea's gross domestic product per capita surpassed $1,000 for the first time last year despite heavy sanctions imposed following a series of nuclear and missile tests, a Seoul-based think tank said Thursday.

Hyundai Research Institute estimated North Korea's nominal GDP per capita at $1,013 in 2015, up from $930 from the previous year, based on its own income analysis model.

The reclusive state's nominal GDP reached $986 in 1987, but has since declined to around $650 in the early 2000s. 

According to the Food and Agriculture Organization of the United Nations, the North produced 4.78 million tons of crops in 2015, a 10.7-percent fall from a year earlier, due to severe drought. The price of rice per 1 kilogram surged 5.6 percent on-year to 5,200 won ($4.73).

Trade with China was valued at $5.71 billion won last year, down 16.8 percent from 2014, mainly due to a drop in the North's exports of natural resources to its largest trading partner.

In contrast, inter-Korean trade rose 15.6 percent on-year to $2.71 billion in 2015, the institute said.

The international community's aid to Pyongyang was tallied at $31.87 million last year, up 12.4 percent from a year ago, but less than 2011's $97.11 million, it noted.

The research institute evaluated the communist state's economic power is equivalent to that of South Korea in the mid-1970s.

North Korea's per-capita GDP lags far behind of other Asian nations, including China ($7,990), Vietnam ($2,088) and Laos ($1,799). It is even below other underdeveloped countries, such as Bangladesh ($1,287) and Myanmar ($1,292), according to the institute.

"North Korea's current economy is not capable of standing alone," said Kim Cheon-koo, a researcher at Hyundai Research Institute. "The wide income gap between South and North Koreas is expected to create massive costs for reunification." (Yonhap)