South Korea for the first six months of the year imported 21 percent less oil -- around 35 million barrels -- from Iran than it did the previous year, reports Bloomberg News, citing customs data.
U.S. Secretary of State Hillary Clinton last month said India, Malaysia, South Korea, South Africa, Sri Lanka, Taiwan and Turkey reduced the amount of crude oil purchased from Iran.
That meant that U.S. sanctions targeting the Iranian energy sector "will not apply to their financial institutions for a potentially renewable period of 180 days," she said in a statement.
Belgium, the Czech Republic, France, Germany, Greece, Italy, Japan, the Netherlands, Poland, Spain and the United Kingdom made similar moves this year.
South Korea wasn't shielded from European sanctions on Iranian oil that went into force July 1.
Sanctions were imposed in response to Iran's nuclear program, which Tehran maintains is for peaceful purposes.
South Korea is the No. 5 oil importer in the world.