Iran's senior nuclear negotiator has welcomed an offer by Russia to enrich Iran's uranium as a positive development.
Chief negotiator Ali Larijani also reiterated Iran's threat to renew enrichment activities if it is referred to the UN Security Council.
Moscow has proposed having Iran's uranium enriched in Russia, then returned to Iran for use in the country's reactors - a compromise that could provide more oversight and ease tensions with the United States and European Union over Iran's nuclear program.
Haggling has continued over the specifics of the proposal, including Tehran's proposal to have China involved in the Russian enrichment process.
After talks with Russian Security Council chief Igor Ivanov, which included discussion of the plan, Larijani told a news conference: "Our view of this offer is positive, and we are trying to bring the positions of the sides closer."