Iranian President Mahmoud Ahmadinejad says a nuclear fuel swap deal Tehran recently reached with Brazil and Turkey is the "last opportunity" to resolve a long-standing nuclear dispute between Iran and the West.

President Ahmadinejad presented his argument with characteristic oratorical verve, saying a nuclear fuel swap deal worked out by Brazil and Turkey last week was a "final opportunity" that must not be lost by the international community.

He says that President Barack Obama should understand that this agreement is a historic chance to show that he wants to create change, to respect the rights of other nations, and to give up what he calls the erroneous policies of past American administrations.

He also appealed directly to President Obama to use his influence to better what he called the "political future of the world" and to oppose those whom he says are counseling Mr. Obama to take a tough stance against Iran.

The United States and other top Western powers have been critical of the recent fuel-swap deal, arguing it does nothing to allay fears that Iran is trying to build nuclear weapons. A similar deal was first proposed last October, when Tehran had a much smaller stockpile of enriched uranium.

Mr. Ahmadinejad also criticized Russia for siding with the United States on a plan to impose a fourth round of U.N. sanctions on Iran. The proposal is being debated in the U.N. Security Council. The resolution appears to have the backing of the Security Council's five veto-wielding permanent members, including China and Russia.

Editor Alex Vatanka of Janes' Islamic Affairs Analyst argues the three main centers of power in Iran, President Ahmadinejad, Ayatollah Ali Khamenei, and the powerful Revolutionary Guard Corps, have conflicting views about the nuclear deal.

"I think it is quite complex, because, whereas the IRGC and the Supreme Leader might have their own survival at stake, Ahmadinejad sees himself differently. He sees himself as the elected official who has to go for the popular vote," Vatanka said. "And he knows that overhauling relations with the United States could really generate some good will in Iran, because, by and large, despite what everyone in the world thinks, there is a lot of pro-American sentiment in Iran. And a lot of people in Iran appreciate that one of the biggest obstacles in improving their lives is the international isolation that they are facing, and that America is crucial in keeping Iran isolated."

Vatanka also believes Iranian Supreme Leader, Ali Khamenei, is not in a strong position to oppose Mr. Ahmadinejad, should he attempt a rapprochement with the United States, and the Revolutionary Guard, while powerful, remains divided among itself.