The visit comes just days after Iran released the South Korean oil tanker, Hankuk Chemi, and its captain following more than three months in detention in the Persian Gulf over alleged violation of ecological standards.
It is the first such trip by a South Korean head of government in 44 years.
South Korean Prime Minister Embarks on Rare Visit to Iran on Sunday
© AP Photo / Kim Hong-Ji/Pool
The release sparked speculation that the two countries might have reached some progress on Iran's frozen 7 billion euros ($8.3 billion) worth of assets. The sides have been discussing for a while how to release at least a part of the funds for the Islamic republic's humanitarian needs.