By Matt Spetalnick and Parisa Hafezi
WASHINGTON/TEHRAN (Reuters) - Iran on Friday welcomed U.S. President Barack Obama's strongest offer yet of a "new beginning" in relations, but called for action, not talk, from Washington.
"The Iranian nation has shown that it can forget hasty behaviour but we are awaiting practical steps by the United States," Aliakbar Javanfekr, an aide to President Mahmoud Ahmadinejad, told Reuters.
"The Obama administration so far has just talked," he added, calling for Obama to make "fundamental changes in his policy towards Iran."
The United States has no diplomatic relations with Tehran, which it accuses of backing militant groups and seeking to develop a nuclear bomb under cover of a civilian atomic power programme -- a charge Iran denies.
In a videotaped message to the Iranian people, Obama went further than he has since taking office on January 20 in extending an olive branch to Tehran.
"My administration is now committed to diplomacy that addresses the full range of issues before us, and to pursuing constructive ties," Obama said.
"This process will not be advanced by threats. We seek instead engagement that is honest and grounded in mutual respect." The message was released to Middle East broadcast outlets to mark the Iranian New Year.
In an unusually swift reaction to Obama's overture, presidential aide Javanfekr said Iran welcomed "the interest of the American government to settle differences."
But he said the Obama administration "should realise its previous mistakes and make an effort to amend them."
"By fundamentally changing its behaviour America can offer us a friendly hand," he told Reuters. "Unlimited sanctions which still continue and have been renewed by the United States are wrong and need to be reviewed."
Javanfekr singled out U.S. backing for Israel, Iran's main enemy in the region, saying that: "Supporting Israel is not a friendly gesture."
Obama has already expressed a readiness to have face-to-face diplomatic contacts with Tehran, a major shift from former President George W. Bush's policy of trying to isolate a country he once branded part of an "axis of evil."
Obama said the United States wanted Iran to take its "rightful place in the community of nations," but also insisted that Tehran do its part to achieve reconciliation.
"You have that right -- but it comes with real responsibilities, and that place cannot be reached through terror or arms, but rather through peaceful actions that demonstrate the true greatness of the Iranian people and civilization," Obama said.
"The measure of that greatness is not the capacity to destroy, it is your demonstrated ability to build and create," he added, alluding to Iran's contested nuclear program and its missile development efforts.
'PEOPLE CONFUSED'
Mohammad Hassan Khani, assistant professor of international relations at Tehran's Imam Sadiq University, described Obama's appeal as a positive gesture but noted it came only a week after the extension of U.S. economic sanctions.
"This is somehow conflicting and making people here confused," he said.
President Mahmoud Ahmadinejad has demanded Washington say sorry for decades of "crimes" against the Islamic Republic. Tehran also says it cannot let down its guard as long as U.S. troops are posted on its borders in Iraq and Afghanistan.
Analysts have said that Iran is setting tough conditions for dialogue with the United States to buy time for its ponderous and opaque decision-making process, which is facing a dilemma on whether or not to open up.
Adding to uncertainty, the Islamic Republic holds a presidential election in June that could strengthen moderate voices backing detente over their more hardline opponents.
Ultimately policy will be determined by Iran's Supreme Leader Ayatollah Ali Khamenei, who tends to seek consensus. Any decision, analysts say, will be based on preserving the system of clerical rule.
European Union foreign policy chief Javier Solana said he hoped Iran would pay close attention to Obama's appeal.
"I hope that that will open a new chapter in relations with Iran," he told reporters before going into an EU summit.
To stress the seriousness of Obama's overture, the White House distributed the videotape with Farsi subtitles and posted it on its website to coincide with Iranian observance of the ancient festival of Nowruz, celebrating the arrival of spring.
But his appeal was not shown nor mentioned on Iran's main 2 p.m. state television news, although it was reported by Iranian news agencies including the official agency IRNA.
Obama made no specific offers, but said he wanted "a future with renewed exchanges among our people and greater opportunities for partnership and commerce."
"This won't be reached easily," he acknowledged.
The United States cut off diplomatic ties with Iran during a 1979-1981 crisis, in which a group of militant Iranian students held 52 U.S. diplomats hostage at the American Embassy for 444 days.
Obama has said the United States is ready to extend a hand of peace to Iran if it "unclenched its fist."
The Obama administration said recently it would invite Tehran to an international conference on Afghanistan later this month. Iran has said it would consider the invitation.