SEOUL (AFP) - North Korea's foreign trade rose to just US$6.8 billion (S$8.6 billion) last year, with China accounting for 90 percent of the total, a state-funded South Korean trade promotion body said on Wednesday.

The 2012 figure was slightly up on the previous year's US$6.3 billion, the Korea Trade-Investment Promotion Agency (KOTRA) said, citing data from its own trade partners.

The North's total exports stood at US$2.9 billion against imports of US$3.9 billion, it said, adding that the North had run a trade deficit since the agency started tallying data in 1990.

About 88.3 percent of last year's trade involved China, compared to 89.1 percent in 2011 and 83 percent in 2010 - a dramatic turnaround from the early 2000s when the figure hovered below 50 percent.

Other notable trading partners include Russia, India and Thailand.

The North has increasingly relied on China - its sole major ally - as its economic and diplomatic isolation has intensified and UN sanctions imposed over its nuclear weapons and missile programmes have tightened.

Exports to China - mostly coal and iron ore - amounted to US$2.4 billion while imports, dominated by crude oil and heavy machinery, stood at $3.5 billion.

"The North has such a limited range of products for export and the global sanctions continue to take a toll," KOTRA said in a statement.