Officials from both sides warned however that success was far from guaranteed.
Such a prospect, however, alarms Iran’s regional rival, Saudi Arabia, and Israel, widely assumed to have nuclear weapons itself and which has lobbied hard to prevent what it sees as too soft a deal.
The Iranian official briefed reporters on the condition that he not be named.
The West wants to keep the arms embargo in place and a senior Western diplomat said a removal was “out of the question”.
The aim of the talks in Vienna is to settle the confrontation over Iran’s nuclear programme, reaching a final agreement by Tuesday.
The United States and its allies worry Iran is utilizing its civilian nuclear programme as a canopy to develop a nuclear weapons functionality.
Israeli Prime Minister Benjamin Netanyahu said the deal being formulated with Iran is worse than the failed agreement with North Korea, which led to a nuclear arsenal there.
It could also reduce the odds of any military strike against Iran’s nuclear facilities, something Washington has refused to rule out, and the possibility of a wider war in the Middle East, where conflicts already rage in Iraq, Syria and Yemen.
Kerry said that’s true, but “at this point, this negotiation could go either way”.
Kerry is trying to find a way to satisfy the Iranians without abandoning the US position that the sanctions should be lifted over several years, in line with Iranian compliance with the deal.
German Foreign Minister Frank-Walter Steinmeier said it would take courage and compromise to reach a deal.
On the US campaign trail, Hillary Clinton said at a college event on Friday night that she hoped the US would reach an agreement by this week’s deadline, and Chris Christie remarked yesterday that while he opposes the nuclear deal, he would not pledge to undo such an agreement if he is elected president.
Kerry is under pressure to nail down the deal by Thursday in order to send it to the Republican-controlled United States Congress for a 30-day review.
But the six powers had yet to agree on a United Nations Security Council resolution that would lift UN sanctions and establish a means of re-imposing them in case of Iranian non-compliance with a future agreement.
Shortly after Kerry’s remarks, he walked back into another meeting with Iranian Foreign Minister Zarif.
“We are not yet where we need to be on several of the most hard issues”, Kerry told reporters Sunday in Vienna, Austria, following one-on-one talks with Iran’s foreign minister, Javad Zarif.
“Two delegations from the IAEA will arrive in Tehran to debate particulars of what was agreed through the IAEA chief’s go to to Iran“, Behrouz Kamalvandi, spokesman for Iran’s Atomic Energy Organisation, advised Iran’s Students News Agency ISNA.
BRIDGET BRENNAN: There are some concessions Iran won’t make – it will still enrich uranium on its soil, and some key infrastructure will still stand.
Iran and world powers are working to finish the latest round of nuclear talks “in the timeframe” that the parties have set out, said U.S. Secretary of State John Kerry in Vienna late Sunday.