South Korea's producer prices remained flat in June as a rise in crude prices was offset by cheaper farm products.

According to the preliminary data by the Bank of Korea on Friday, the producer price index, a barometer of future consumer inflation, reached 104-point-41 last month, unmoved from May. 

From a year earlier, it rose two-point-six percent to mark the 20th consecutive month of on-year growth, stretching back to November 2016.

The index of agricultural and fishery products fell three-point-three percent on-month in June, the largest drop since October last year. 

However, prices of industrial goods, petrochemicals and gas gained point-two percent on-month in June. The growth narrowed from the point-four percent gain recorded in May, as the increase in crude oil prices slowed slightly last month. 

Despite the slowing growth, crude oil prices still remain significantly higher compared to 2017, as they soared 47 percent in May and nearly 60 percent in June from a year ago.