The Bank of Korea(BOK) on Thursday slashed its key interest rate in a surprise move designed to help stimulate growth.

The central bank slashed its policy rate by a quarter percentage point to one-point-five percent just eight months after it raised the rate by 25 basis points to one-point-75 percent.

The cut comes amid sluggishness in exports and a delay in the parliamentary passage of a supplementary budget bill, as well as concerns that Japanese trade restrictions may further dampen the economy.

Exports have contracted every month since December last year and inter-party political strife has kept the extra budget bill from moving forward.

Earlier, BOK Governor Lee Ju-yeol had hinted at a possible cut of the key rate amid trade tensions between the U.S. and China, but Thursday's move comes sooner than many anticipated.

The central bank also marked down its economic growth outlook for this year from two-and-a-half percent to two-point-two percent. It also slashed its estimate for this year's inflation rate from one-point-one percent to point-seven percent.