A senior Iranian official claimed Thursday that a breakthrough had been made at nuclear talks in Geneva, and that Tehran's proposed plan for resolving the impasse over its atomic program has been accepted by the six world powers. At roughly the same time, Israel's prime minister, Binyamin Netanyahu, warned that signing an interim deal with Iran would be a mistake of “historic proportions,” but that appears to be precisely the deal being hammered out.

Abbas Araqchi, Iran's deputy foreign minister, said the so-called P5+1 powers had "accepted the framework of Iran's proposal.”

"The aim of both sides is to sign the agreement," he told Iranian journalists after the first session of talks, adding that further progress was expected at a scheduled meeting on Thursday evening.

"We hope we can all reach an agreement on a single text and that an agreement would be signed between two sides. We are currently working on this issue but it is too early to say if we will have a written agreement or it will be deferred to the next meeting or the next ones," Araqchi said. "It's too early to say whether a written agreement could be made in the next 48 hours."

The British Guardian called his account of progress at the talks "the most upbeat from a Iranian official in many years.” It is believed the Iranian framework involves signing an interim partial deal that would slow down or stop key elements of the progress of Iran's nuclear activity in return for limited sanctions relief. That would “buy time” for a more comprehensive deal, to be negotiated over the course of a year, which would set long-term limits for the Iranian program.

In another sign of progress, the leader of the Iranian delegation, Foreign Minister Javad Zarif, cancelled a trip to Rome so that he could take part in Thursday evening's face-to-face meeting with the EU foreign policy chief, Catherine Ashton, who acts as the convenor for the six-nation negotiating group that includes the US, UK, France, Germany, Russia and China.

In addition, reorted the Guardian, the format of the talks in the afternoon were changed in an attempt to make possible more rapid progress. Araqchi said both sides agreed to hold four brief sessions in the afternoon instead of the usual long sessions. Iran will meet France, Britain and Germany in one session and Russia, China and the US in three separate afternoon sessions.

Netanyahu: historic mistake

Prime Minister Binyamin Netanyahu denounced on Thursday the proposals reportedly being made in Geneva regarding Iran's nuclear program, saying adopting them would be "a mistake of historic proportions."

Speaking at a conference on joint strategic dialogue between the government of Israel and the Jewish world, Netanyahu said the proposals being offered at the meeting would ease pressure on Iran for empty concessions that would "allow Iran to retain the capabilities to make nuclear weapons."

He added that ongoing sanctions have seriously affected the Iranian economy, and the P5+1 can compel the nation to fully dismantle its nuclear weapons program.

Netanyahu called for "ending all enrichment, stopping all work on the heavy water plutonium reactor. Anything else will make a peaceful solution less likely."

He reiterated that Israel "reserves the right to defend itself, by itself, against any threat."

Netanyahu met Thursday evening with a visiting delegation of members of the US Congress and told them, "If the news that I am receiving of the impending proposal by the P5+1 is true, this is the deal of the century, for Iran. Because Iran is essentially giving nothing and it's getting all the air taken out, the air begins to be taken out of the pressure cooker that it took years to build in the sanctions regime.

“What we're having today is a situation that Iran is giving up, at best, a few days of enrichment time, but the whole international regime's sanctions policy has the air taken out of it. That's a big mistake, it will relieve all the pressure inside Iran, it is a historic mistake, a grievous historic error.”

Iranian state TV aired a documentary this week showing the country's ability to fire missiles on Tel Aviv and Foreign Minister Zarif said Wednesday that the West should forget armed action, saying negotiations were the only option.

Analysis has shown that Iran's acquisition of a nuclear weapon would be a huge destabilizing factor in the Middle East, with some suggesting that Saudi Arabia's oil fields would be a first target.