* April Iran crude imports at 516,918 T vs 552,884 T yr ago
* Buys 117,161 bpd from Iran in Jan-April, down 13.8 pct y/y
* Jan-April Iran oil imports below 2014 import average
* Total April crude imports at 10.5 mln T, up 10.7 pct y/y
By Meeyoung Cho
SEOUL, May 15 (Reuters) - South Korea's imports of Iranian crude fell 6.5 percent in April from a year ago, with its oil shipments from the OPEC country in the first four months of 2015 dropping nearly 14 percent year-on-year to meet international sanction requirements.
South Korea and other Asian buyers can import crude form the Islamic nation at sanctions-reduced rates reached at the end of 2013, with the United States and five other world powers facing a June 30 deadline for a final deal with Iran on curbing its nuclear programme.
Seoul imported 516,918 tonnes of crude oil from Tehran last month, or 126,300 barrels per day (bpd), compared with 552,884 tonnes, or 135,088 bpd, a year ago, preliminary customs data from the world's fifth-largest crude oil importer showed on Friday.
Asia's No.4 economy brought in 1.9 million tonnes, or 117,161 bpd, of crude from the Middle Eastern country in the period between January and April this year, below 2.2 million tonnes, or 135,982 bpd, in the same period last year.
South Korean crude shipments from Iran in 2014 were 6.2 million tonnes, or 124,497 bpd, down 7.1 percent from the 2013 average of 134,000 bpd, according to data and Reuters calculations in January.
Of South Korea's four refiners, only SK Energy Co Ltd and Hyundai Oilbank Co Ltd import Iranian oil, and their imports fluctuate each month.
Meanwhile, South Korea imported 416,335 tonnes, or 101,725 bpd, from Mexico in April, paying $47 per barrel on average, according to Reuters calculations based on the customs data.
Seoul shipped in 135,707 tonnes, or 32,088 bpd, of Mexican crude in March as GS Caltex Corp bought the oil for the first time in 25 years to take advantage of low prices.
Mexican state oil company Pemex, which said earlier this year that it sold a total of 5 million barrels of crude to South Korea and hopes to double sales by the end of this year, said on Thursday it had signed a contract with Hyundai Oilbank to sell 5 million barrels of crude.
Overall, South Korea imported 10.5 million tonnes of crude last month, or 2.49 million bpd. That was 10.7-percent higher than the 9.5 million tonnes imported in April of 2014, the customs data showed.
Final data for last month's imports, which will include greater detail, will be available from state-run Korea National Oil Corp later this month. (Editing by Joseph Radford)