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* Imports 1.24 mln T of Iranian crude in April, down 12.1 pct y/y
* Jan-April oil imports from Iran drop 34 pct to 4.69 mln T y/y
* Russian April crude imports more than double to 1 mln T y/y
* April total crude imports at 11.59 mln T, up 2.5 pct on-year
By Jane Chung
SEOUL, May 15 (Reuters) - South Korea’s crude oil imports from Iran fell 12.1 percent in April from a year ago, while imports of Russian oil more doubled, customs data showed on Tuesday.
South Korea imported 1.24 million tonnes of Iranian crude, or 303,025 barrels per day (bpd), in April, down from 1.41 million tonnes from last year, according to the customs data.
The world’s fifth-biggest crude oil importer has increased its imports of Iranian crude, mainly condensate, or an ultra-light oil since sanctions were lifted in 2016.
However, imports have fallen this year, partly reflecting a cut in supplies to South Korea by the National Iranian Oil Co due to lower production and the start of a new splitter, sources have said.
Worries had also been growing about the potential reimposition of U.S. sanctions against Iran, which U.S. President Donald Trump announced on May 8, spurring some South Korean buyers to replace imports of Iranian condensate.
South Korean refiner Hyundai Oilbank made its first purchase of Norwegian condensate, while SK Incheon Petrochem said it would continue to buy light crude including from Russia and Kazakhstan.
In the first four months of this year, South Korea’s intake of Iranian oil dropped 34 percent to 4.69 million tonnes, or 286,308 bpd, versus about 7.1 million tonnes over the same period a year ago, the data showed.
In total, South Korea’s April crude oil imports were 11.59 million tonnes, or 2.83 million bpd, up 2.5 percent from 11.30 million tonnes from 2017, according to the data.
April crude imports from Saudi Arabia, South Korea’s top crude oil supplier, fell 6.9 percent to 3.32 million tonnes, or 810,564 bpd, from last year.
Meanwhile, South Korea imported 1.01 million tonnes from Russia in April, or 33,689 bpd, up 132.4 percent from 434,974 tonnes last year, according to the data.
For the January-April period of this year, South Korean brought in 48.29 million tonnes of crude, or 2.95 million bpd, up 0.2 percent from 48.18 million tonnes in the same period in 2017.
Final data for the country’s April crude imports data will be released by state-run Korea National Oil Corp (KNOC) later this month.
Reporting By Jane Chung; editing by Richard Pullin