"We are ready to examine proposals by the other side about the fuel swap," Mottaki told IRNA.
Mottaki's comment came after Iran's proposal on how to provide fuel for a research nuclear reactor in Tehran was rejected by Washington.
The United States dismissed earlier this month an offer to swap on the Iranian island of Kish 400 kilogrammes (880 pounds) of low-enriched uranium for nuclear fuel enriched to 20 percent, in what would be the first phase of a deal with world powers.
Mottaki reiterated a mid-December statement that Iran did not "insist on" the Kish plan.
"The objective to offer that proposal was to open a way for the other side."
President Mahmoud Ahmadinejad told AFP on Friday that Iran was ready to strike a uranium enrichment deal if the United States and the West respect the Islamic Republic and stop making threats.
Iran is under three sets of UN sanctions for refusing to suspend enrichment and risks a further round after rejecting a UN-brokered deal to send its low enriched uranium abroad to be further refined into fuel for its research reactor.
Enrichment lies at the heart of fears over Iran's atomic work as the process to make nuclear fuel can also be used to make the fissile core of an atom bomb in much higher purifications.
Iran insists its nuclear programme is solely for civilian purposes and rejects Western suspicions that it is covertly trying to develop a bomb.
