Iran's top nuclear negotiator Ali Larijani on Thursday charged the US with undermining talks on Russia's proposal to enrich uranium for Tehran.
The US' insistence on referring Iran to the UN Security Council over its nuclear activities "speaks of the demolition of the Russian proposal," Larijani told journalists.
Iranian negotiators on Wednesday reopened talks on a compromise solution to the escalating crisis around Tehran's nuclear programme.
As the UN nuclear watchdog, the International Atomic Energy Agency (IAEA), prepares to deliver a report on Iran on March 6, Tehran had agreed in principle to the joint venture to enrich uranium on Russian territory.
But it still wants to maintain its own uranium enrichment programme at its Natanz plant.
Enriched uranium is used to fuel nuclear power plants but the West fears that Iran has a secret nuclear weapons programme and plans to use higher grade enriched uranium to make atomic bombs.
Uranium enriched in Russia would be designated for use at the Bushehr nuclear power plant that Russia is currently completing for Iran and in other planned power stations.
The Russian proposal might be the last chance for the Islamic state to avoid final referral to the UN Security Council and possible economic sanctions.
{{/usCountry}}The Russian proposal might be the last chance for the Islamic state to avoid final referral to the UN Security Council and possible economic sanctions.
{{/usCountry}}During a visit to Hungary this week, Russian President Vladimir Putin said he still held high hopes of sealing a deal with Iran.