The P5+1 countries - the five permanent members of the U.N. Security Council, the U.S., the U.K., France, Russia, China, plus Germany - and Iran have agreed on the major parameters of the ongoing nuclear talks. With this agreement, the possibility of the removal of economic sanctions on Iran, one of the most important countries in the region, will undoubtedly have major economic consequences. However, before anything else, I must underline that this is a tentative agreement, which means that both sides do not have enough mutual trust in each other. So, let us look at ways of making this tentative situation permanent and sustainable.

At the beginning of the agreement process, there were around a hundred points of dispute. It is difficult to say whether these points have been eliminated completely, but for the time being, the parties have entered a process of mutual trust. Undoubtedly, Turkey will play a key role in the establishment of this trust in the upcoming period. Therefore, President Recep Tayyip Erdoğan's visit to Iran this week is of great significance. As is known, Turkey took a major step together with Brazil in 2010 with the vigorous efforts of the-then Prime Minister Erdoğan. The agreement that was reached as a result of the efforts of Erdoğan and the Brazilian President Lula da Silva in 2010, included important articles for the solution of the issue. However, the West was not as prudent as Erdoğan and Lula, an error which resulted in great loss of time. So, the current tentative agreement does not go beyond the one that was reached in 2010. After Hassan Rouhani was elected president and Iran's supreme leader Ali Khamenei endorsed it, the nuclear negotiations between Iran and the West were resumed in September 2013 and the parties agreed on a framework convention on April 2, 2014. This convention prioritized economic pressure on Iran at a time when U.S. President Barack Obama wanted to bring the negotiations to a conclusion before the 2016 elections.

In order to make this agreement permanent, the West should take Turkey into consideration and Iran should acknowledge that it cannot permanently improve its economy without Turkey. Erdoğan spoke of this reality to both sides in 2010. Now, Iran needs Turkey so that it can be a serious alternative to the EU market, apart from Russia, and that its energy potential can be evaluated more strongly. On the other hand, with the removal of the embargo, Turkey will develop industrial trade and mutual investment with Iran and will talk about the politically contentious issues, including the Syria and Yemen crises, on a more healthy ground. The removal of sanctions on Iran means access to Iran's frozen financial assets, but such assets can be evaluated only via Turkey. So, it would be much easier for Iran if it prefers Istanbul to Riyadh or Dubai, and this would be a reasonable path both for the West and Tehran.

On the other hand, Turkey's prioritization of the Southern Gas Corridor (SGC) in energy does not only include Caspian resources, it will also comprise Iraqi Kurdistan's and the Mediterranean's resources in the course of time. In this sense, the SGC will be an important energy export route for Iran as wellbwhen the West-Iran agreement becomes permanent. Apart from this, both the West and Iran need Turkey so that this agreement will be valid for commercial transits as well.

Today, there are three major routes connecting Asia Pacific to the European market. They are critical commercial transits that complement each other and provide economic integration between Asia and Europe. They are predominantly railway lines, as railway transportation, particularly high-speed railway lines, is more advantageous than other alternatives in terms of speed, price and security. The three major corridors that connect developing Asia, particularly China, to Europe are as follows:

The Northern Corridor: It passes through the Russian mainland along the Trans-Siberian line and reaches Europe passing through Kazakhstan and Belarus, both of which Russia has been in a customs union with since 2010. After the Crimean crisis, the Northern Corridor contains significant political disadvantages for the West.

The Middle Corridor: This route reaches Europe passing though China, Kazakhstan, Turkmenistan, Caspian Sea (by ferry), Azerbaijan and Turkey.

The Southern Corridor: It starts from Kazakhstan and passes through the Turkmenistan-Iran-Turkey line. When we look at these lines, which will constitute the new Silk Road and connect Asia and Europe, we see that the middle and southern corridors are inevitably important for Europe and the U.S. for the actualization of the Transatlantic Trade and Investment Partnership (TTIP). In other words, if the Southern Corridor does not operate, the nuclear deal will not work either. The operation of this line and the SGC depends on Turkey and its stability. Considering all this, both the West and Iran should look to Erdoğan and do what he says if they want to make this agreement permanent.