South Korea's foreign exchange reserves have exceeded the 200 billion dollar mark for the first time, backed by a rise in investment profits.

The Bank of Korea announced Thursday that as of Wednesday, the nation's foreign reserves stood at some 225 billion dollars, up 550 million dollars from the end of January.

The central bank attributed the unprecedented surge to an increase in investment profits, including interest payments from the U.S. Treasury Department.

The nation's foreign reserves have been continuously on the rise since September 2001, when the figure surpassed one-hundred billion dollars and climbed to 1.5 billion dollars in November 2003.

South Korea ranks fourth in the world in terms of foreign reserves following Japan, China and Taiwan.