Turkish President Recep Tayyip Erdogan has arrived in Iran as Ankara and Tehran assess how to respond to the Kurdish independence referendum in Iraq.
Erdogan was greeted at the Mehrabad airport on October 4 by Mohammad Shariatadari, Iran's minister of industry and mining.
Iranian President Hassan Rohani is due to welcome Erdogan officially later in the day. Erdogan is also scheduled to meet Iran's supreme leader, Ayatollah Ali Khamenei, during his visit.
Both Turkey and Iran -- along with Iraq and other regional powers -- are opposed to an independent Kurdish state in northern Iraq.
Turkey has several thousand ground forces stationed in northern Syria and Erdogan has warned he will not accept a Kurdish state along his borders.
The Iraqi government has demanded that the Kurdistan regional government (KRG) cancel the result of the September 25 referendum or face continued sanctions, international isolation, and possible military intervention.
After the nonbinding September 25 referendum, in which 95 percent of the 3.3 million people voting favored independence, the Kurdish autonomous region said on October 3 that it was calling presidential and parliamentary elections for November 1.
Baghdad, which had already imposed sanctions on Kurdish banks and halted foreign currency transfers to the region, responded with further punitive measures.
Ahead of the Kurdish referendum, Iran's army and Revolutionary Guard launched a military exercise in the country's heavily Kurdish northwest.
In addition to the Kurdish referendum, the crisis in Syria is also expected to be discussed. Turkey and Iran are both part of the Astana process to reduce violence in Syria, along with Russia.
Turkey has backed rebel forces, while Tehran supports President Bashar al-Assad.