A deal has been reached between the world powers and Iran over the latter’s nuclear program after a series of major American concessions, Ehud Yaari, the Middle East affairs commentator for Israel’s Channel 2 television, said Friday night. “It is done. It is done,” he said, and will be signed “early next week.”

The aim of the agreement is to put a negotiated end to a 13-year standoff with Iran over its suspect nuclear program and to block its pathway to developing a nuclear bomb in exchange for lifting biting global sanctions. Israel’s leadership has relentlessly opposed the emerging agreement, with Prime Minister Benjamin Netanyahu warning that it will pave Iran’s path to a nuclear arsenal.

According to Yaari, Israel’s most respected Middle East analyst, the deal was reached because the Americans “have made a series of capitulations over the past two to three weeks in almost every key aspect that was being debated.”

Yaari said that even those in the US who had supported the agreement with Iran “admit that it is worse than they thought.” Now, he said, the ball is in the court of Democratic lawmakers who have to decide whether to support their president as he seeks to secure Congressional approval, or to join the vocal Republican opposition to an agreement.

Ehud Yaari (photo credit: Courtesy)

Ehud Yaari (photo credit: courtesy)

One major concession, Yaari said, is the issue of inspections of Iranian nuclear sites, which has long been a sticking point in the negotiations. According to Yaari, the US negotiators have given in to an Iranian demand that inspections are “managed” — in other words, there will be no surprise visits, only those that are pre-arranged and approved by the Iranian regime.

While there has been no official word that the deal is finalized, US Secretary of State John Kerry said Friday evening that progress had been made in the talks, and praised what he called the “constructive” atmosphere.

“I think we have resolved some of the things that were outstanding and we’ve made some progress,” he said, speaking to a few reporters as he met with his team of experts in Vienna.

Meetings have been happening all day, Kerry said, adding: “We have a couple of different lines of discussion that are going on right now.”

“The atmosphere is very constructive,” he told the reporters who travelled with him from Washington.

“We still have a couple of very difficult issues, and we’ll be sitting down to discuss those in the very near term – this evening and into tomorrow.”

The talks are now heading into their third weekend in Vienna. Kerry met Friday morning with his Iranian counterpart Mohammad Zarif in an effort to close remaining gaps.

The terms of a 2013 interim accord under which Iran has suspended much of its uranium enrichment in return for some sanctions relief were extended to Monday in a bid to overcome a deadlock.

France’s Laurent Fabius and British Foreign Secretary Philip Hammond are also due to return to the Austrian capital Saturday in the hopes of advancing the deal.