Still, he sounded a cautious note on the looming US decision, noting South Korea's possibility of being branded as a manipulator cannot be ruled out.

He said South Korean officials have explained Seoul's financial market conditions and factors driving up trade surpluses during meetings with officials from the US government and the International Monetary Fund.

South Korea was put on a monitoring list by the US Treasury Department last year due to a significant bilateral trade surplus with the United States and other factors.

The US government is expected to unveil a list of currency manipulators in April.

Lee stressed the importance of taking steps beforehand to make sure the US will not designate Seoul as a currency manipulator.

Separately, Lee called for measures to keep household debt from rising further at a time when interest rates are set to rise.

South Korea's outstanding household credit -- which is composed of household loans and credit card spending -- came to 1,344.3 trillion won ($1.19 trillion) at the end of 2016, up 11.7 percent from a year earlier.

Last week, the US Federal Reserve raised its key rate by a quarter of a percentage point to a target range of 0.75 to 1 percent. It also signaled that additional hikes would be made in a gradual manner later this year.

The BOK maintained its policy rate at an all-time low of 1.25 percent for the eighth consecutive month in February to support the growth of Asia's fourth-largest economy. The BOK has no monetary policy meeting in March. (Yonhap)