Iran nuclear talks: comprehensive deal inches closer

European and Chinese officials are pushing for a deal on Iran’s nuclear programme to be signed on Monday, but Washington and Tehran – the two main protagonists at the negotiations in Vienna – will not be rushed.

The Chinese foreign minister, Wang Yi, told reporters that his team “believes that no agreement could be perfect, and conditions are already in place for us to reach a good agreement,” as he joined his counterparts for the endgame of the negotiations. “We believe that there cannot, and should not, be further delay.”

This latest round of talks got under way in the Austrian capital 17 days ago, though negotiations between the international community and Iran over the country’s atomic aspirations have been held on and off for 12 years.

European diplomats at the talks said on Sunday that the major obstacles to a deal had been cleared away and that they expected an announcement on Monday afternoon, but their American counterparts were more cautious. They distributed logistics information to US journalists covering the negotiations about the choreography of events after an announcement, but a senior state department official insisted “major issues” remain.

Meanwhile, the Iranian delegation also suggested the talks were not yet at the finish line. Its foreign minister, Mohammad Javad Zarif, said: “We believe there shouldn’t be extension but we can continue working by the time that it’s necessary.” Zarif’s deputy, Abbas Araqchi, said: “I cannot promise whether the remaining issues can be resolved tonight or tomorrow night. Some issues still remain unresolved and, until they are solved, we cannot say an agreement has been reached.”

Diplomats in Vienna suggested that one reason for the delay was that neither the US nor the Iranian delegations wanted to present the White House or the supreme leader a deadline for completing their review of the final text. However, going beyond midnight on Monday would require a 2013 interim deal to be rolled over for the fourth time in a fortnight, to keep a freeze on sanctions and the Iranian nuclear programme in place

Even after a deal is announced, it would take some hours for the text of the agreement, the English version of which stretches to more than 80 pages, including five annexes, to be “scrubbed” or proofread and reviewed by lawyers. Translations would then have to be completed before the final text was sent to the relevant capitals for approval by national leaders.

Under the expected settlement, Iran will accept curbs on its nuclear programme in exchange for extensive sanctions relief. Tehran would also have to subject its facilities to a more rigorous inspections regime. It would represent a historic compromise after a 12-year standoff that has at times threatened to provoke a new conflict in the Middle East. In a statement issued on Sunday, a senior US State Department official said: “We have never speculated about the timing of anything during these negotiations, and we’re certainly not going to start now, especially given the fact that major issues remain to be resolved in these talks.”

The British foreign secretary, Philip Hammond, returned to the UK for unspecified reasons. Diplomats said he was expected back on Monday and suggested his departure meant that the main political decisions had been taken as far as the UK was concerned, leaving mostly technicalities to finalise. Over the weekend, Iranian officials had said that the UK and Germany had made forceful arguments about their own red lines, and that was confirmed in the British case by western diplomatic sources. Their concerns appeared to have been resolved by Sunday evening.

Once an agreement is announced, it will not take effect for some time. It must first survive a trial by fire from its critics in Washington and Tehran. The greatest hurdle will be the US Congress, where Republicans have a majority and are expected to vote against the deal after a review period of up to 60 days. They will seek to win over 12 Democrats in an attempt to defeat a presidential veto.

Mitch McConnell, the Senate majority leader, described the expected deal as “a very hard sell”. Bob Corker, the Republican head of the Senate foreign relations committee, told NBC: “At the end of the day I think people understand that if this is a bad deal that is going to allow Iran to get a nuclear weapon, they would own this deal if they voted for it, and so they’ll want to disapprove it. On the other hand, if we feel like we’re better off with it, people will look to approve it.”

The European and Chinese foreign ministers have come and gone over the course of the talks and even Zarif left for a day, but John Kerry remained in Vienna throughout. It is the longest time that a US secretary of state has spent abroad in a single location dealing with a single issue since the aftermath of the second world war.

Kerry has also conducted the gruelling fortnight of diplomacy, including repeated late-night meetings, on crutches after a bicycle accident in May. On Sunday morning he attended mass in Vienna’s 14th-century St Stephen’s Cathedral, where Mozart was married and Vivaldi’s funeral was held. Speaking about a late-night meeting with Zarif hours before, he said: “I think we’re getting to some real decisions. So I will say, because we have a few tough things to do, I remain hopeful.”

The French foreign minister, Laurent Fabius, told reporters as he rejoined the talks on Sunday afternoon: “I hope we’re arriving finally at the last phase of these marathon negotiations. I believe so.”

The road ahead

Although the deal could be agreed and published as early as Monday, it will be months before it starts to come into effect. A number of steps have to be taken first:

• The US Congress will have two months to review the agreement, and then an extra 22 days are set aside for voting, a possible presidential veto, and then another vote to see if opponents can muster 67 Senate votes to override the veto. At the same time, Iran’s parliament, the Majlis, will study the deal and issue its own verdict, but has no firm timetable.

• Assuming it survives legislative scrutiny, the agreement will be codified and incorporated in a UN security council resolution, which will also lift UN sanctions on Iran, conditional on Tehran taking its agreed steps to reduce its nuclear infrastructure. Some Iranian sources say the resolution will come earlier in the process, while the deal is still under legislative review.

• Iran will then begin to disconnect centrifuges, remove the core from its heavy-water plant and reduce its stockpile of low-enriched uranium. The International Atomic Energy Agency will monitor and verify the steps taken. Iran will also work with the IAEA to resolve unanswered questions about alleged past nuclear weapon design work.

• At the same time, Barack Obama will grant waivers on economic and financial sanctions, and the EU will vote to lift European sanctions. Both sets of sanctions relief will be made contingent on IAEA confirmation that Iran has upheld its side of the bargain.

• In a final step, possibly around the end of the year, economic and financial sanctions will be lifted, and an enhanced IAEA inspections regime will be implemented, routinely monitoring Iran’s fuel cycle from uranium mines to enrichment and fuel manufacture, and visiting undeclared sites.