Iran and six world powers will extend through the end of June 2015 talks on Tehran's nuclear program after failing to clinch a final agreement that could end a 12-year atomic dispute, British Foreign Secretary Philip Hammond said on Monday.
He told reporters that Iran and the powers "made some significant progress" in the latest round of talks, which began last Tuesday in the Austrian capital.
Hammond added that there was a clear target to reach a "headline agreement" of substance within the next three months and talks would resume next month.
It is unclear where next month's talks will take place, he said, noting that during the extension period, Tehran will be able to continue to access around $700 million per month in sanctions relief. An Iranian official confirmed the extension.
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The talks in Vienna aimed for a deal that could transform the Middle East, open the door to ending economic sanctions on Iran and start to bring a nation of 76 million people in from the cold after decades of hostility with the West.
The cost of failure to reach a deal could be high. Iran's regional foes Israel and Saudi Arabia are watching the Vienna talks nervously. Both fear a weak deal that fails to curtail Tehran's nuclear ambitions, while a collapse of the negotiations would encourage Iran to become a threshold nuclear weapon state, something Israel has said it would never allow.
It became increasingly clear during a week of intensive negotiations between the top U.S. and Iranian diplomats that what officials close to the talks have been predicting privately for weeks will likely be correct: barring a last-minute decision by Iran to compromise, a final deal is still too far off to hammer out by the parties' self-imposed deadline later on Monday.
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The United States, Britain, France, Germany, Russia and China began the final round of talks with Iran on Tuesday to clinch a pact under which Tehran would curb its nuclear work in exchange for lifting economically crippling sanctions.