Iran's Irna news agency said Elham had advised it that Ahmadinejad planned to attend "if the Security Council has a meeting on Iran's nuclear programme".
Iran, the world's fourth-biggest oil exporter, has ignored UN demands that it should halt its uranium enrichment and insists its aim is to generate nuclear power.
The Security Council imposed a package of limited sanctions on Iran in December, including a ban on the transfer of sensitive nuclear technology and knowledge.
It threatened further steps if Iran failed to meet its February 21 deadline to suspend enrichment.
The six world powers are considering new measures, but both China and Russia have resisted the idea of financial sanctions.
Mohammad Ali Hosseini, an Iranian foreign ministry spokesman, said: "We believe that if they follow an extreme way it won't help find a logical and legal solution but we cannot give up our obvious right (to nuclear technology)."
Hosseini repeated Iran's call for negotiations to end the standoff.
He said: "We have always suggested that if the other side has any ideas or solutions which are in the framework of regulations and which guarantee Iran's rights, they can discuss them and the best place for that is the negotiating table."
A draft of new measures being considered against Iran could further expand a list of people, firms and groups whose assets would be frozen or with whom trade would be restricted, such as Iran's Revolutionary Guards and the state-owned Bank Sepah.