Iranian President Mahmoud Ahmadinejad urged the U.S. Wednesday to join talks on a nuclear fuel swap deal, reiterating that Tehran was ready to start talks near the end of the month.

Ahmadinejad also repeated an offer to hold talks with U.S. President Barack Obama on "global problems" at the U.N. General Assembly in September, although
Washington has rebuffed his proposal.

"He (Obama) missed the opportunity last year for a fuel swap; today this opportunity is on the table again," Ahmadinejad said in a televised speech in the city of
Hamedan in western Iran .

"We are ready for talks based on respect, justice and
Iran 's proposals after mid-Ramadan (late August) and we advise him (Obama) not to miss this opportunity," Ahmadinejad said.

Iran said Sunday it was seeing a "positive" feedback from the Vienna group-- U.S. , Russia and France--over the proposal brokered by Brazil and Turkey to supply Tehran with nuclear fuel.

The May 17 proposal by
Iran , Turkey and Brazil , known as the Tehran Declaration, stipulates that Iran send 1,200 kilogrammes (2,645 pounds) of its low-enriched uranium to Turkey in return for 20% high-enriched uranium to be supplied by Russia and France at a later date.

The world powers led by
Washington had previously cold-shouldered the plan, and backed a fourth round of U.N. sanctions against Iran on June 9.