Iran said on Monday it would not hinder any Turkish bid to mediate between the Islamic Republic and the new U.S. administration but cautioned that its differences with Washington were deep-rooted. (UPDATED)

Turkey is ready to be the mediator between the new Obama administration and Iran, using its growing role in the Middle East to bridge the divide between East and West, Turkish Prime Minister Tayyip Erdogan told the New York Times earlier this month.
The U.S. and Iran have not had diplomatic ties for three decades and are now embroiled in a row over Tehran's nuclear program.
"We think the comments ... stem from Turkish goodwill and good and growing neighborly ties between Iran and Turkey, so we will certainly not raise any obstacles," Iranian Foreign Ministry spokesman Hassan Qashqavi said when asked about Erdogan's remarks.
"But the reality is that the issue and problems between Iran and the United States go beyond the usual political problems between two countries," he was quoted by Reuters as telling a news conference.
Relations with Iran will be one of U.S. President-elect Barack Obama's main foreign policy challenges when he takes office in January. He has said he would harden sanctions but has also held out the possibility of direct talks.
Iranian officials have reacted cautiously to Obama's election, saying it reflects the American people's desire for fundamental change in U.S. policies at home and abroad but that it remains to be seen whether he will live up to expectations.
The United States severed ties with Iran shortly after its 1979 Islamic revolution and is now spearheading efforts to isolate the country over sensitive nuclear work the West suspects is aimed at making bombs, a charge Tehran denies.
"Around 30 years after the ... revolution the Americans have had negative performance towards us," Reuters quoted Qashqavi as saying. "Mr Obama has come forward with slogans and now we will have to see whether the change in orientation is serious or not."
Iranian President Mahmoud Ahmadinejad congratulated Obama after his Nov. 4 victory, but other officials in Tehran later criticized the U.S. president-elect's call for an international effort to stop Iran developing a nuclear bomb.
Iran, the world's fourth-largest crude oil producer, says its nuclear program is aimed at generating electricity.
Like outgoing U.S. President George W. Bush, who branded Iran part of an "axis of evil", Obama has not ruled out military action although he has criticized the outgoing administration for not pushing for more diplomacy and engagement with Iran.
Iran has said it would respond to any attack by targeting U.S. interests and Washington's ally Israel, as well as closing the Strait of Hormuz, a vital route for world oil supplies.
Erdogan said Ankara watched relations between Iran and the United States with great concern and that Ahmadinejad's note of congratulation to Obama was "a step that has to be made use of".
The United Nations has placed sanctions on Iran over a nuclear program that the U.S. and other nations say is working to the development of nuclear weaponry. Iran says the program is peaceful.
Turkey supports the position of its Western allies but argues that the sanctions are weakening Iranian reformists. Turkey is against any country in the region developing nuclear weapons but believes it is Iran's legitimate right to use nuclear energy for peaceful means.
Turkey fears an economically and politically isolated Iran, which supplies it with its principal alternative to Russian energy. It also wants to avoid another military conflict on its borders.