By Paul Reynolds
World Affairs correspondent, BBC News website
Iran is still managing to avoid being reported to the Security Council over its nuclear activity and the diplomatic entanglement is likely to continue for some time to come.
Iran faces the threat of sanctions over its nuclear activities
Behind the scenes there is an intense struggle going on between an Iran determined to preserve its right to develop a nuclear fuel cycle and a West trying to stop it.
The outcome is in doubt.
Iran is nervous about going too far, too fast, in case it is referred to the Security Council and told to stop.
The West, however, lacks the diplomatic muscle to bring the weight of the Council to bear.
Now a new major player has come onto the stage - Russia. And this entry will prolong the whole drama.
Meanwhile Iran and the three European Union countries, the "EU3" - Britain, France and Germany - are dancing around each other about whether to resume "consultations" which could lead to a resumption of talks broken off in the summer.
All this emerged from the board meeting in Vienna this week of the International Atomic Energy Agency (IAEA), the UN's nuclear regulatory agency.
It is not clear how far Ahmadinejad wants to push the West
Russia has proposed a compromise between Iran's insistence that it has a right under the Nuclear Non-Proliferation Treaty to develop a nuclear fuel cycle, and Western demands that it give up this right in view of its past effort to conceal an enrichment programme.
The compromise would let Iran do more or less what it can at present - convert uranium ore first into refined "yellowcake" and then into a gas ready for the enrichment process.
The actual enrichment, however, would be carried out in Russia at a plant to be constructed for the purpose.
So now Russia and Iran will deal face to face on this issue.
The deal would save some Iranian face in that it would not be stopped altogether and it would enable the West and Russia to claim that Iran was not learning how to enrich uranium. This is important because the enrichment technology can be used for military as well as peaceful purposes.
There is no doubt that Iran is playing a skilled game. Not that it has had things all its own way in the last two years.
It was caught out trying to develop a secret uranium enrichment capability and has since concentrated on mending its bridges with the IAEA by allowing inspections and giving up documents.
But it has also manoeuvred successfully to stop the United States and the EU from taking the issue to the Security Council. The IAEA agreed in principle in September that this could happen. But it has not agreed in practice.
IRAN'S NUCLEAR STANDOFF
September 2002: Work begins on Iran's first nuclear reactor at Bushehr
December 2002: Satellite photographs reveal nuclear sites at Arak and Natanz. Iran agrees to an IAEA inspection
September 2003: IAEA gives Iran weeks to prove it is not pursuing atomic weapons
November 2003: Iran suspends uranium enrichment and allows tougher inspections; IAEA says no proof of any weapons programme
June 2004: IAEA rebukes Iran for not fully co-operating with nuclear inquiry
November 2004: Iran suspends uranium enrichment as part of deal with EU
August 2005: Iran rejects EU proposals and resumes work at Isfahan nuclear plant
The Council could impose economic sanctions on the grounds that Iran's past secrecy and current lack of transparency means that it has lost its right under the Nuclear Non-Proliferation Treaty to enrich fuel.
The problem for the West is that it cannot muster enough support in the IAEA to get the referral agreed and, even if the matter got to the Security Council, there is no guarantee that Russia and China would agree to sanctions.
China is said to be sympathetic to the call for Iran to stop enrichment and its delegate warned Iran "to co-operate", otherwise the issue "handled inappropriately, could get out of the framework of the IAEA and worse, the situation could get out of control". But how far it would take this attitude is not clear.
One Western official has been quoted as saying: "We don't hold many cards."
A glimpse of the manoeuvring became evident in Vienna with the circulation among reporters of a four-page intelligence document attributed to Western agencies.
This claimed that Iranian officials have discussed the start of enrichment activity at the underground plant at Natanz. This would take Iran a stage further down the enrichment path than the conversion it says it has restarted at Isfahan.
The document claimed that all the details surrounding such work had been discussed on 24 October. However, nobody knows when or even if this might all happen. The new President Mahmoud Ahmadinejad is taking a hard line internally but it is not clear how far and fast he wants to push the nuclear issue.
Another sign of the pressure Western countries are putting on the IAEA came with a statement from the British ambassador to the IAEA, Peter Jenkins.
He concentrated on the possible implications of an Iranian admission that it had received (it says it was simply given this and did not ask for it) a document from the renegade Pakistani nuclear scientist A Q Khan detailing how to use uranium to construct an atomic bomb.
"Does Iran's possession of this document put Iran in breach of Article II of the NPT which states, inter alia, that non-nuclear-weapon states undertake not to seek or receive, I emphasise receive, any assistance in the manufacture of nuclear weapons or other nuclear explosive devices?" Mr Jenkins asked.
For its part, Iran continues to counter with comments of its own. The influential cleric Akhbar Hashemi Rafsanjani said that the latest IAEA discussions did in some ways "betray a vestige of harassment".
"We will never accept being bullied," he said.
The diplomatic dance goes on.