The foreign ministers of France and Germany joined the top US and Iranian diplomats yesterday to help break an impasse in nuclear negotiations as major powers and Iran closed in on a two- or three-page accord that could form the basis of a long-term deal.

The negotiations, in progress for nearly 18 months, aim to hammer out an accord whereby Iran halts sensitive nuclear work in exchange for the lifting of sanctions, with the ultimate aim of reducing the risk of a war in the Middle East.

US Secretary of State John Kerry and Iranian Foreign Minister Mohammad Javad Zarif have been in Lausanne for days to try to reach an outline agreement by a self-imposed deadline of March 31, and they held a further round of talks yesterday.

While Tehran and the six major powers – the United States, Britain, France, Germany, Russia and China – could clinch the preliminary framework accord in the coming days, several sticking points remain that could prevent a deal, officials close to the talks said.

“I hope we can get a robust agreement. Iran has the right to civil nuclear power, but with regard to the atomic bomb, it’s ‘no’,” French Foreign Minister Laurent Fabius told reporters on his arrival in Lausanne.

“We have moved forward on certain points, but on others not enough,” he said.

Iran denies any ambition to build nuclear weapons and says its atomic programme is for purely civilian purposes.

We have moved forward on certain points, but on others not enough

German Foreign Minister Frank-Walter Steinmeier compared the talks in Lausanne to the final stage of a mountain climb.

“The endgame of the long negotiations has begun,” he told Reuters. “And here, with a view of the Swiss mountains, I’m reminded that as one sees the cross on the summit the final meters are the most difficult but also the decisive ones.”

Before taking an afternoon bike ride, Kerry lunched with Fabius and Steinmeier to discuss the remaining obstacles to a deal.

The two European ministers were also set to meet Zarif as Western and Iranian officials familiar with the negotiations cautioned that they could still fail.

“The sides are very, very close to the final step and it could be signed or agreed and announced verbally,” a senior Iranian official familiar with the talks told Reuters.

Ahead of meeting Zarif, Kerry said he expected the discussions to run late. Zarif added that the meetings would run through “evening, night, midnight, morning”.

The British, Russian and the Chinese Foreign Ministers were due to arrive today.

If agreed, the document would cover key numbers for a comprehensive agreement between Iran and the six powers, such as the maximum number and types of uranium enrichment centrifuges Iran could operate, the size of uranium stockpiles it could maintain, the types of atomic research and development it could undertake and also details on the lifting of international sanctions that have crippled Iran’s economy.

Two officials said it was likely that most of the outline agreement would be made public.

Others said certain sections would be kept confidential.

Several Iranian officials denied that Iran was close to agreeing an outline document but a Western diplomat said such comments were aimed at a domestic audience.

Sign up to our free newsletters

Get the best updates straight to your inbox:
Please select at least one mailing list.

You can unsubscribe at any time by clicking the link in the footer of our emails. We use Mailchimp as our marketing platform. By subscribing, you acknowledge that your information will be transferred to Mailchimp for processing.