The jump is associated with South Korea’s interest in cheap Iranian condensate that prompted Asia's major ultra-light oil buyer to boost purchases of the oil products last month.
Figures released by Reuters show that Seoul brought in 1.04 million tons of Iranian crude oil last month, or 254,653 barrels per day (bpd).
The volume is more than two times higher than 485,182 tons that the country imported a year earlier when sanctions were imposed on Tehran.
South Korea – which is the world's fifth-largest crude oil importer - brought in 6.12 million tons, or 246,522 bpd, of crude from Iran in the first half of this year. That was almost 108 percent higher than 2.95 million tons in the same period in 2015, according to the data provided by the country’s customs office.
Reuters has added in its report that Seoul was expected to increase imports of oil from Iran in June as two refiners - SK Energy and Hanwha Total Petrochemical Company - were set to lift at least 6 million barrels of Iranian South Pars condensate (SPC), up from about 3 million to 4 million barrels in April and May.
More Iranian condensate imports are expected in the fourth quarter if Iran signs a deal with Hyundai Chemical to supply the company's new 110,000-bpd splitter in Daesan on the country's west coast, which would be completed in the second half of the year, Reuters added.