Tehran  - Iran's Supreme Leader Ayatollah Ali Khamenei on Saturday rejected an offer by US President Barack Obama to open a new era in relations until Tehran could see real changes in US policies.

"The new US president sends us a Persian New Year greeting message but in the same accuses us again to support terrorism and to be after nuclear weapons," the supreme leader said in a televised speech in the city of Mashad in north-eastern Iran.

"He offers us his hand with a velvet glove under which, however, might be a cast-iron hand," Khamenei added.

"We will not accept any offer for negotiations which goes together with force ... we will see and if you [President Obama] really change, then we will change as well. But the aims and not just the tactics should be changed," Khameinei added.

The cleric, in line with Iran's constitution, has the final say on all state affairs.

Obama, in a video message on the occasion of the Persian New Year, said Friday the United States was committed to engagement, not threats, in its pursuit of diplomacy.

The US president said it could not be a one-sided effort, suggesting the people of Iran also "have a choice" about whether they take their "rightful place in the community of nations."

"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, in a video m essage broadcast by the Voice of America's Persian News Network. (dpa)