VIENNA—Key elements of a landmark nuclear agreement between Iran
and six world powers were falling into place Sunday, but U.S.
Secretary of State John Kerry warned there were important sticking
points that may yet scuttle the deal.
Mr. Kerry said the Obama administration could walk away from the
negotiations if Iran proves "intransigent" on the remaining issues
by Tuesday, the new deadline for a comprehensive agreement aimed at
blocking Iran's ability to move swiftly toward nuclear weapons in
exchange for easing tight international sanctions.
Senior U.S. and Iranian officials said advances have been made
on two of the thorniest issues: the pace of sanctions relief for
Iran and a United Nations investigation into charges that Tehran
has secretly developed nuclear weapons technologies in recent
decades.
European Union foreign-policy chief Federica Mogherini said late
Sunday that a final agreement, which has taken more than a decade
of diplomacy, was now "very close."
However Mr. Kerry played down expectations of an imminent
breakthrough.
"It is now time to see whether or not we are able to close an
agreement," Mr. Kerry said. "But I want to be absolutely clear: We
are not yet where we need to be on several of the most difficult
issues," he added.
"If hard choices get made in the next couple of days—and made
quickly—we could get an agreement this week. But if they are not
made, we will not."
Mr. Kerry said he agreed with Iranian Foreign Minister Javad
Zarif's assessment on Friday that the two sides have never been
closer to a deal, but added: "At this point, this negotiation could
go either way."
By Sunday evening, Ms. Mogherini, the French, Russian, German
and British foreign ministers were all back or headed back to
Vienna, where Mr. Kerry and Mr. Zarif continued negotiations over
the weekend.
The head of the U.N.'s nuclear watchdog said Saturday that he
had agreed with Iran's leadership to conclude an investigation into
Tehran's alleged suspected nuclear weapons work by the end of the
year.
"With the cooperation from Iran, I think we can issue a report
by the end of the year on the assessment of the clarification of
the issues related to possible military dimensions," Yukiya Amano,
director general of the International Atomic Energy Agency or IAEA,
told reporters in Vienna shortly after returning from Iran.
Mr. Amano said Friday that more work would be needed to flesh
out details of how Iran would take forward the discussions with the
agency. Late Sunday, the IAEA confirmed that senior officials were
traveling back to Tehran for fresh talks.
Oil-rich Iran insists its nuclear program is purely for peaceful
purposes such as generating electricity.
The IAEA has been seeking Iranian responses to 12 sets of
questions it first raised in 2011 about Iran's past nuclear work,
based on evidence suggesting Iran may have been developing nuclear
weapons technology. The IAEA says that despite promising closer
cooperation in November 2013, Iran has so far only partially
addressed two of those sets of questions.
The agency says that to date, Tehran has balked at requests to
interview key Iranian scientists and to visit alleged nuclear
sites.
Iran and the U.S. have also made progress in recent days in
addressing the tricky issue of sanctions relief, according to
senior U.S. and Iranian officials.
Iran's Supreme Leader Ayatollah Ali Khamenei has publicly
demanded most economic and financial sanctions on Tehran be
immediately lifted at the time of an agreement. But Iranian
negotiators in the past few days have committed in Vienna to a
phased approach, where sanctions will be lifted as Iran takes
specific steps to roll back its nuclear program.
That includes disconnecting centrifuge machines which enrich
uranium—a process that can be used to produce fuel for both nuclear
energy or nuclear weapons. Other steps are drastically reducing the
country's stockpile of enriched uranium and reconverting its heavy
water reactor in the city of Arak so it produces less
weapons-usable plutonium.
"On a certain date, Iran will start doing its share, and at the
same time, the Americans and the Europeans will commit themselves
to terminate sanctions at a certain point," a senior Iranian
official said last week. "So the commitment is made beforehand, and
the actual termination will happen on the date that Iran will have
finished its work."
A senior U.S. official had warned on Friday evening that the
July 7 deadline could slip, as the two sides try to narrow
differences on several key issues including access to Iranian
military sites, Iran's nuclear research rights under a deal and
details of Iran's cooperation with the IAEA.
Mr. Kerry and Ms. Mogherini both said Sunday that they wanted a
deal done by July 7 although Mr. Kerry refused to rule out more
talks after that date.
If Iran and the world powers meet the July 7 deadline, it would
mean the U.S. Congress would only get 30 days to review an
agreement. However, if no deal is reached before July 9, the U.S.
legislature would have an additional 30 days to look over the
accord. That would give skeptics more time to rally opposition.
Appearing to anticipate an agreement in Vienna, leaders of the
Republican party in Washington stepped up attacks over what they
said were going to be weak terms.
Speaking to CBS on Sunday, Sen. Robert Corker (R, Tenn), the
chairman of the Senate Foreign Relations committee who crafted the
key legislation giving lawmakers a vote on the Iran deal, said the
Obama administration must ensure the IAEA wins anytime, anywhere
inspections under a final deal.
"I did talk to Secretary Kerry yesterday. I urged him to please
take their time. Try to make sure that these last remaining red
lines that haven't been crossed—they have crossed so many—do not
get crossed and qualitatively they don't' make it worse than where
it already is."
Israeli Prime Minister Benjamin Netanyahu accused the six-power
group negotiating with Iran of caving in to Iranian demands.
"What is emerging in the nuclear talks is not a breakthrough but
a breakdown," Mr. Netanyahu said Sunday during his weekly cabinet
meeting. "The deal that is being formulated will pave the path of
Iran to create cores of many atomic weapons. It will also enable
the flow of hundreds of millions of dollars that will serve the
same aggression and its terror campaign—both in the region and
throughout the world."
Josh Mitnick in Tel Aviv contributed to this article.
Write to Laurence Norman at laurence.norman@wsj.com and Jay
Solomon at jay.solomon@wsj.com
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