South Korea's foreign reserves hit a new high for the seventh straight month due to a rise in investment returns, central bank data showed Wednesday.

Foreign reserves reached a fresh record high of 348.39 billion U.S. dollars at the end of January, up 1.93 billion dollars from a month earlier, according to the Bank of Korea (BOK).

The figure was the new monthly high, keeping its record- breaking trend for the seventh consecutive month. The country's foreign reserves stayed above the 300-billion-dollar mark since April 2011 when it topped the level for the first time.

The nation's foreign reserves consisted of 318.86 billion dollars of securities, 18.73 billion dollars of deposits, 4.79 billion dollars of gold bullion, 3.49 billion dollars of special drawing rights and 2.52 billion dollars of International Monetary Fund positions.

As of the end of December, South Korea was the world's seventh- largest holder of foreign reserves following China, Japan, Switzerland, Russia, China's Taiwan and Brazil.