Turkish President Recep Tayyip Erdogan is in Tehran for high-level meetings expected focus on strengthening trade and economic relations.
Heading a high-ranking delegation, Erdogan met with President Hassan Rohanion on April 7.
He was later due to hold talks with Supreme Leader Ayatollah Ali Khamenei.
The visit comes in spite of recent tensions between the neighbors over a Saudi-led military operation against Shi’ite Huthi rebels in Yemen.
Erdogan has publicly supported the air strikes against Yemen's Iran-backed Huthis, and accused Tehran of trying to "dominate the region."
Iran denies it is helping militarily the rebels in Yemen, which President Abd-Rabbu Mansour Hadi was forced to flee two weeks ago.
Diplomatic relations between Turkey and Iran have also suffered in recent years over disagreements over how to resolve the civil war in Syria.
The two countries have kept strong economic ties, however, and Iran is Turkey's second-largest supplier of natural gas.