Iran is already subject to UN sanctions over its nuclear work
Further sanctions against Iran over its nuclear plans are unlikely, a senior Russian official has said.
President Dmitry Medvedev's adviser Sergei Prikhodko said sanctions on Iran "are unlikely in the near future", Russian news agencies reported.
His comments came as Iranian officials said they would respond to a proposal by the UN's nuclear watchdog about exporting uranium on Thursday.
The West fears that Iran is seeking nuclear weapons, but Iran denies this.
Tehran says it wants enriched uranium only for civilian use, including energy.
Iran is already subject to UN sanctions, including financial scrutiny and restrictions on arms exports, for enriching uranium at its Natanz plant.
The UN's nuclear watchdog, the International Atomic Energy Agency (IAEA), has suggested exporting most of Iran's enriched uranium to Russia and France, where it would be converted into fuel before being returned to Iran.
The plan was agreed by the US, Russia and France, after talks in Vienna, but Iran missed a deadline on Friday to respond.
Iran's Mehr news agency reported that Iran's negotiator at the IAEA, Ali Asghar Soltaniheh, would meet IAEA chief Mohamed ElBaradei on Thursday and "give Iran's response to the Vienna talks".
European Union foreign policy chief Javier Solana was expected to speak to Iranian officials on Wednesday about the deal, AFP news agency reported.
He had previously said it was "a good deal" and did not require "fundamental changes".
Iranian state media reported a day ago that Iran wanted "very important changes" made to the deal before it would be accepted.
Under the draft proposal, Iran would send its enriched uranium to Russia and France to be turned into fuel.
All the other parties have confirmed their support for the deal, which is seen as a way for Tehran to get the fuel it needs for an existing reactor, while giving guarantees to the West that its enriched uranium will not be used for nuclear weapons.
Air defence missiles
Meanwhile, Russia's deputy Prime Minister Sergei Ivanov said S-300 air defence missiles - Russia's most advanced anti-aircraft weapon - had not yet been supplied to Iran.
Iran indicated in 2007 that it would buy the S-300.
Asked by reporters in the Russian town of Fryazino when Russia would deliver the missiles to Iran, Mr Ivanov said on Wednesday: "There have been no such deliveries to date."
The S-300 missiles would be defensive, according to Russia. Israel - Iran's arch-foe - fears they will be used to defend nuclear facilities.
Washington wants all countries to stop exporting weapons to Iran, but Russia and China have opposed such a move.