* U.S. seeks "critical choices" from Iran in nuclear dispute
* Extension of negotiations is possible for up to 6 months
* But Western diplomats say progress needed for extension
* Zarif: Iran's team will work hard for deal in coming days
(Adds Kerry quotes, White House statement, EU comment)
By John Irish and Fredrik Dahl
VIENNA, July 14 U.S. Secretary of State John
Kerry said he held good and serious talks with his Iranian
counterpart on Monday as the two sides raced to narrow wide gaps
on Tehran's nuclear programme less than a week before a July 20
deadline to reach a deal.
Seeking to push Iran to make "critical choices" over its
disputed atomic activities, Kerry met Mohammad Javad Zarif for
a second day running with both sides complaining ahead of the
gatherings that scant progress had been made.
"We are working. We are working very hard. A lot of serious
discussions. It was a good meeting," Kerry told reporters after
ending a session with Zarif and European Union foreign policy
chief Catherine Ashton.
They are trying to bridge major differences in negotiating
positions over a deal intended to end a decade-long dispute over
a nuclear programme which Tehran says is peaceful. The West
fears it may be aimed at developing nuclear weapons capability.
In Washington, the White House said Iran had engaged with
Western powers in a serious way, but had yet to make the
decisions necessary to prove that the programme was peaceful.
Spokesman Josh Earnest, asked whether Kerry was authorised
to extend the deadline, said he was assessing Iran's positions
and would return to the United States to make recommendations to
President Barack Obama on how to proceed.
A senior U.S. State Department official said Kerry, Ashton -
who is coordinating discussions with Iran on behalf of six world
powers, including the United States - and Zarif had a "lengthy
and productive meeting", but that more work was required. It was
unclear whether Kerry and Zarif would meet again on Tuesday.
The powers, also grouping Britain, China, France, Germany
and Russia, want Tehran to significantly scale back its nuclear
enrichment programme to make sure it cannot yield nuclear bombs.
Iran's priority is to get sanctions that have severely
damaged its oil-dependent economy lifted as soon as possible.
With the differences over pivotal issues including Iran's
enrichment capacity still large, some diplomats and experts have
said a deal by July 20 is unlikely and that the sides will need
to extend the negotiating period.
However, Ashton's spokesman Michael Mann told reporters that
they were still trying to strike a deal by the target date.
"We are determined to try and get an agreement by July 20.
There are still significant gaps and we are trying to narrow
those down ... we still have some time. There is a text and
there are still brackets around the main issues."
Before Monday's meetings, a senior State Department official
said Kerry wanted to "gauge Iran's willingness to make the
critical choices it needs to make".
Kerry said on Sunday there were still substantial
differences with Iran on how to curb its nuclear fuel-making
capacity, a view Iranian and other Western officials echoed.
Earlier, a senior U.S. official said Iran was sticking to
"unworkable and inadequate" positions.
A history of hiding sensitive nuclear work from U.N.
inspectors has kept international suspicions about Iran's
nuclear programme high and heightened the risk of a new Middle
East war should diplomacy fail to yield a long-term settlement.
EXTENSION OF TALKS?
Zarif said on Sunday after his meeting with Kerry that "our
team is ready to work with full speed during the seven remaining
days in order to reach a comprehensive deal that can be
acceptable for both sides".
But with the two sides so far apart there was little
optimism that an agreement could be signed by next Sunday. The
thorniest issue, diplomats close to the talks say, is the size
of Iran's future enrichment programme.
"It will be difficult to have an agreement in a week," a
senior Western diplomat said. "The Iranians would have to budge
on the key issues and very quickly. There are a lot of technical
aspects that would be difficult to complete in a week."
There is a possibility that the talks on a long-term
settlement could be extended for as long as six months.
A Nov. 24 preliminary agreement between Iran and the six
powers included a provision for lengthening talks on a permanent
agreement as far out as next January if all sides agree. But
even an extension would have to be negotiated.
"The question will be, do we continue to talk and for how
long?" the Western diplomat said.
A senior U.S. official said on Saturday that an extension
would be difficult to consider without first seeing "significant
progress on key issues".
Western officials have said that major hurdles include
enrichment, Iran's stockpiles of nuclear material and answering
U.N. inspectors' questions about its past atomic research that
Western powers and analysts suspect was linked to weapon-making.
French Foreign Minister Laurent Fabius on Sunday publicly
raised the possibility of extending the talks, though British
Foreign Secretary William Hague said it was too early to discuss
the idea of an extension.
(Additional reporting by Parisa Hafezi, Lesley Wroughton, and
Louis Charbonneau; Writing by Louis Charbonneau; Editing by Mark