South Korea's producer prices declined for the 13th straight month in October as oil prices fell and the local currency strengthened against the U.S. dollar, the central bank said Monday.

The producer price index, a barometer of future consumer inflation, slid 1.4 percent in October from a year earlier, compared with a 1.8 percent on-year decline in September, according to the Bank of Korea (BOK).

On an annual basis, the producer prices have fallen every month since October 2012, when such prices fell 0.5 percent on-year.

Prices of Dubai crude, South Korea's benchmark, fell 3.1 percent in October from a year earlier, compared with a 2.9 percent on-year decline in September. The Korean won appreciated 3.76 percent to the greenback in October compared with a year earlier.

Compared with a month earlier, the producer prices inched down 0.4 percent after falling 0.1 percent on-month in September.

The data came as the BOK froze the key interest rate at 2.5 percent for the sixth straight month in November.

Korea's consumer prices remained subdued, running below the central bank's 2.5-3.5 percent inflation target band for 2013-2015.

Korea's consumer inflation grew 0.7 percent in October from a year earlier, the slowest pace in 14 years, due to falls in prices of farm products. (Yonhap News)