Bank of Korea Governor Lee Ju-yeol said changing interest rates in response to moves in the won may have unexpected results.
Lee also said a stronger won is negative on growth but positive on inflation.
Still, investors stayed cautious over possible intervention by the foreign authorities to stem appreciation in the second-best performing emerging Asian currency so far this year.
Most emerging Asian currencies held firm as the Chinese yuan gained despite a weaker midpoint set by the central bank, with investors welcoming Beijing's continued economic stimulus measures.
Thailand's baht rose as traders covered short positions as the currency found a chart support at 32.52 per dollar, a 100-day moving average.
Bank of Thailand Governor Prasarn Trairatvorakul said that the current policy rate level was already low and still supporting economic growth.