Turkish President Abdullah Gul left for Iran on Tuesday to participate in a regional cooperation summit in Iranian capital Tehran and tried to ease tension between Tehran and Washington, the semi-official Anatolia news agency reported.

Gul is set to partake in the 10th Summit of Heads of State and Government of Economic Cooperation Organization (ECO) member states on Tuesday and Wednesday, said the report, adding that he is expected to try persuading Iran to seize the opportunity to resolve the nuclear dispute through talks since a new administration that favors dialogue is in office in Washington.

Gul's visit comes right after U.S. Secretary of State Hillary Clinton's visit to Turkey and ahead of the planned visit of President Barack Obama.

Clinton said during her Sunday visit in Ankara that the U.S would ask Turkey to help push forward President Obama's plan to engage Iran, adding that Obama administration valued Gul's upcoming Iran visit.

Meanwhile, Iran said it had sought Turkey's assistance in talks with the United States.

Turkey is not currently an official mediator between Iran and the United States. However, Turkish Foreign Minister Ali Babacan said on Sunday before departing for Iran to attend a regional meeting that Turkey would consider requests by the two sides to serve as a mediator.

Turkey is against proliferation of nuclear weapons but does not welcome sanctions, including military ones, against Iran, saying the dispute between Iran and the West over its nuclear program should be resolved through diplomatic means.

During his stay in Tehran, Gul is expected to meet with Iran's spiritual leader, Ayatollah Ali Khamenei, and President Mahmoud Ahmadinejad, said the report.

The ECO is an inter-governmental regional organization established in 1985 by Turkey, Iran and Pakistan for the purpose of promoting economic, technical and cultural cooperation among the member states.

Iranian Foreign Ministry spokesman Hassan Qashqavi said over the weekend that Azerbaijan, Pakistan, Tajikistan, Turkmenistan, Iraq and Afghanistan's presidents, as well as Qatar's emir, were planning to attend the summit.

(Xinhua News Agency March 10, 2009)