0251 GMT May 25, 2019
Last month, South Korea was granted the exemption by the US, allowing it to continue to purchase Iranian oil, Yonhap reported.
The two sides held talks to follow up on the measure in Washington DC on Tuesday (local time), according to the ministry.
South Korea's inter-agency delegation was led by Hong Jin-wook, the director general of the ministry's African and Middle Eastern Affairs bureau.
His counterpart was David Peyman, deputy assistant secretary of state for counter threat finance and sanctions.
They discussed "technical issues, including finance, shipment and insurance to support transactions of the trade sector", the ministry said.
Hong requested the US offer 'clear guidelines' on specific targets of Iran sanctions as swiftly as possible, citing a possible gray area.
Peyman agreed to work closely with South Korea via diplomatic channels.
The South Korean team also included representatives from the Finance Ministry, the Trade Ministry and the Financial Services Commission.