The surplus, the broadest measure of South Korea's trade with the rest of the world, totalled $5.82 billion last month, down from a revised $5.91 billion in September.

The September reading was nearly double the figure for August, thanks to growing exports to Southeast Asia and China offsetting slowing demand from Europe.

South Korea's current account has now been in the black for nine consecutive months, having last posted a deficit in January.

For the first 10 months of the year, the surplus stood at $34.1 billion, surpassing the central bank's full-year forecast of $34 billion.

The health of the current account and heavy foreign fund inflows have seen the Korean won gain about 9.0% against the dollar since May -- a worrying trend for an export-driven economy already struggling with the downturn in its US and European markets.

The government announced Tuesday it was lowering the ceiling on foreign exchange forward positions by foreign and local banks, to ease currency volatility.