US, Iran in new nuclear talks as tempers fray

Iran and the US aim in talks starting Sunday in Switzerland to begin closing in on a milestone deal reducing Tehran's nuclear activities to within strict limits after 18 months of tortuous negotiations.
Time is however running very short and tempers are fraying in Washington where critics fear that the mooted accord will not do enough to prevent the Islamic Republic getting the bomb.
US Secretary of State John Kerry, due to meet his Iranian counterpart in Lausanne, sought to allay such concerns on the eve of talks, saying the aim was "not just to get any deal, it is to get the right deal".
The target is for Iran and six world powers -- the US, Russia, China, Britain, France and Germany -- to agree the outlines of a deal by March 31 and to fine-tune the details by July 1.
Kerry said he hoped an interim agreement could be clinched in the coming days.
"We believe very much that there's not anything that's going to change in April or May or June that suggests that at that time a decision you can't make now will be made then," Kerry told CBS television.
"My hope is that in the next days that will be possible," he added during the interview recorded in Egypt on the eve of a new round of talks in Switzerland.
The interview, excerpts of which were provided by the network, was due to air in full on Sunday on CBS's "Face the Nation" program.
Kerry, speaking during a three-day international investor conference in the Egyptian resort town of Sharm el-Sheikh, said that if Iran's nuclear program is indeed "peaceful," as Tehran claims, "let's get it done."
Iran's supreme leader, Ayatollah Ali Khamenei, has however criticised the two-step process, saying matters should be handled in one fell swoop.
Khamenei is due to give a closely watched Iranian New Year's address on March 21. On Thursday he said the other side in the talks was "deceitful and stabs in the back".
- Rouhani thaw -
The US and Iran have not had diplomatic relations for 35 years and the standoff over Tehran's nuclear programme has dogged its international relations for more than a decade.
But the 2013 election of President Hassan Rouhani resulted in a minor thaw and the past 18 months have seen an intense diplomatic effort to resolve the issue.
Under a November 2013 interim deal, Tehran stopped expanding its activities in return for minor sanctions relief. Since then the parties have been pushing for a lasting accord.
But to the alarm of Israel and US Republicans, the US has abandoned insisting that Iran dismantles all nuclear activities, tolerating instead a small programme under tight controls.
In theory, this still leaves Iran with the possibility to get the bomb, critics say, and last week 47 Republicans took the unprecedented step of writing an open letter to Iran's leaders.
They warned that any nuclear deal could be modified by Congress or revoked "with the stroke of a pen" by whomever succeeds President Barack Obama, a Democrat, in 2017.
This followed a barnstorming address to US lawmakers -- on a Republican invitation -- by Israeli Prime Minister Benjamin Netanyahu warning against a deal.
Republicans have also threatened to bring draft legislation imposing more sanctions towards the end of March, something which would likely prompt Iran to walk away.
The letter provoked a storm in Washington with Vice President Joe Biden calling it "dangerous" and the State Department saying it was "harmful to American security."
Obama said in a Vice media interview to be released Monday that he was "embarrassed" for the signatories, while Washington's allies in its talks with Iran were also unimpressed.
"The negotiations are difficult enough, so we didn't actually need further irritations," German Foreign Minister Frank Walter Steinmeier said last week.
And Iranian Foreign Minister Mohammad Javad Zarif told top clerics: "In truth, it told us that we cannot trust the United States."
- Third extension? -
Some progress has been made towards a final deal but the two sides remain far apart on several key issues.
These include the future size of Iran's uranium enrichment capacities -- which can make nuclear fuel but also the core of a bomb -- the pace at which painful UN, US and EU sanctions would be lifted and the accord's duration.
"We made some progress, but there are still some gaps, important gaps," Kerry said in Egypt on Saturday.
Two deadlines, in July and November, passed without an agreement but in view of the controversy in Washington -- and pressure in Iran on Rouhani to deliver -- extending yet again will be very tough.
"There is no time for additional extensions," said Kelsey Davenport, an analyst at the Arms Control Association.
"After March, it becomes much more difficult to hold off legislative attempts to by Congress to sabotage the deal," Davenport told AFP.