South Korea's foreign exchange reserves rose to a new high last month on the weakening of the U.S. dollar.

According to the Bank of Korea on Monday, the total value of the country's foreign exchange reserves came to 408-point-82 billion dollars at the end of December, up one-point-36 billion dollars from a month earlier.

The monthly foreign exchange reserves have posted new high records for three straight months since September last year. 

The central bank said that the depreciation of the U.S. dollar increased the value of non-dollar currencies when converted into the greenback.

South Korea was the world's ninth-largest holder of foreign exchange reserves at the end of November, with China topping the list, followed by Japan and Switzerland.