Tehran  - Iran had no hostility toward the United States but requires signs of amity to put an end to three decades of diplomatic estrangement, ex-president Akbar Hashemi-Rafsanjani said at a Friday prayer ceremony in Tehran.

"We have no hostility with the American nation, but there should be some signs of goodwill to change the status quo," said Rafsanjani, who still plays an influential role in the Iranian political scene as head of the Experts Assembly, a powerful religious body.

US President Barack Obama, in a video message March 20 on the occasion of the Persian New Year, offered a new chapter in bilateral ties, saying the United States was committed to engagement, not threats, in its pursuit of diplomacy with Iran.

Iran's supreme leader, Ayatollah Ali Khamenei, rejected the offer until Tehran could see real change in US policies.

"The leader was right as the changes should be shown in practice - the release of the frozen Iranian assets could be a first step in this regard," Rafsanjani said.

Since the establishment of the Islamic republic in Iran and the collapse of the monarchy in 1979, the United States has frozen Iranian assets in American banks that are said to amount to more than 20 billion dollars.

The United States has further stopped delivery of important spare parts that Iran had ordered before the revolution, especially parts for Iranian passenger planes.

Khamenei, who in line with Iran's constitution has the final say on all state affairs, said that if Obama really implemented his proclaimed changes, then Iran would also change its policies toward the new US administration.

The first step for the rapprochement could be Tuesday's Afghanistan conference in The Hague. Iran has confirmed its attendance, although on what level was not yet clear.

Despite grave differences over numerous issues, Iran and the United States hope to have at least a fruitful cooperation on both Afghanistan and Iraq.

Especially in Afghanistan, both countries share common interests: a common enemy in the Taliban and a common friend, the government of President Hamid Karzai.

Observers said they believe that improvement in Iran-US ties could also lead to a breakthrough in the dispute over Iran's controversial nuclear programmes. (dpa)