Syria as sticking point

In Rouhani's first trip to Turkey since he became president last year, the key goals are improving bilateral relations and signing various treaties - as announced by the Iranian ambassador in Ankara, Ali Reza Bikdeli. Above all, future economic and trade cooperation are at the top of the agenda, the Turkish newspaper "Today's Zaman" writes.

Turkish Prime Minister Recep Tayyip Erdogan visited Iran this past January. During Rouhani's visit, Erdogan emphasized doubling the trade volume between the two nations, to around 22 million euros ($30 million).

But a significant political sticking point remains: since the start of the civil war in Syria, Iran has taken the side of Bashar al-Assad. Turkey supports the opposition.

The Syria snag

Hakan Günes, a professor of political science and international relations at Istanbul University, said that the political situation in Syria is the biggest problem between Iran and Turkey. The two countries are fighting a proxy war in Syria, he said.

"Assad and Hezbollah are fighting for Iran against Turkish allies - those would be the Free Syrian Army, the Islamists and jihadists," Günes said. Despite this, the two nations are still able to carry on with their formal relations, he added.

In addition to that, Turkey's mediator role in Iran's nuclear program indicates the country is trying to position itself as a regional leader. "For years, Erdogan has attempted to take a leadership role in the Islamic world, and in the Middle East," Günes said. But Iran remains a significant force there, he added.

The international embargo against Iran makes free trade a practical impossibility, Günes clarified. The only way Tehran can carry out trade would be to cooperate with Persian Gulf states and Turkey - which aren't participating in the sanctions, he pointed out.

Economic interconnectedness

Regardless of widespread compliance with the sanctions against Iran, every Western country is also seeking ways to profit indirectly from Iranian markets, Günes said. Some German, French, and American companies have parallel companies in Turkey under different names, which makes Turkey a kind of bridge between the West and Iran. "The Turkish economy also profits from this," Günes explained.

An economic point of contention is the price of natural gas - Ankara has complained for years about the high price of gas imports from Iran. "Today's Zaman" reported that there's been little progress on this front, based on information from Turkey's energy ministry.

Future energy cooperation is likely to top the priorities for the present visit. The Ukraine crisis, for example, has driven home a need to seek out energy from non-Russian sources for the European Union and United States.

In terms of fossil fuels, Iran continues to hold a key global position: it has the world's fourth largest oil reserves, and the world's largest natural gas reserves. But due to longtime US and United Nations sanctions intended to derail Iran's nuclear ambitions, Iran has not been able to sell its oil and gas to the West. Turkey, acting as a gateway for distribution of Iran's energy resources, is likely to bring the two countries closer together, Günes said.

Out of isolation?

Rouhani is considered to be a reformer, who is trying to bring Iran out of isolation, said Fethi Acikel, a political scientist at Ankara University. "He's trying to normalize relations with the West, and stabilize his country's image," Acikel told DW, adding that the Iranian president is doing this through economic cooperation.

Turkey's governing AK Party has already promised to support Iran, despite its isolation from the West. Their common Islamic roots help explain why, Acikel added. "The Islamic-conservative AKP considers Iran to be a reliable partner," he concluded.