US, Iran Nuclear Deal in Balance as John Kerry, Javad Zarif Meet

Muscat: Iran and the United States held a second day of talks on Monday in Oman about a long hoped for nuclear deal, with key differences threatening to scupper a final agreement.

With a November 24 deadline hanging over the negotiations, US Secretary of State John Kerry and Iran's Foreign Minister Mohammad Javad Zarif are laying out their nations' competing demands, but with no signs of a breakthrough.

As they first met in Muscat on Sunday, US President Barack Obama underlined the high stakes of the encounter, saying that a "big gap" remains on how the West can have "verifiable, lock-tight assurances" Iran cannot obtain a nuclear weapon.

The Iranian delegation, meanwhile, is under pressure to deliver a total lifting of US, UN and European sanctions under a final deal, something they want immediately but which Obama said would only be "slowly reduced" if Tehran meets its obligations.

"We may not be able to get there," Obama told CBS News.

Kerry and Zarif's talks resumed just before 11.30 am (0730 GMT). Only one day of negotiations had been originally scheduled.

The key sticking point is thought to be the number and type of uranium-enriching centrifuges Iran should be allowed to keep spinning in exchange for sanctions relief and rigorous inspections of its nuclear sites.

Big differences remain

Iran denies it is seeking a bomb and says its nuclear programme is solely aimed at producing atomic energy to reduce the country's reliance on fossil fuels, requiring a massive increase in its ability to enrich uranium.

The duration of a final settlement between Iran and the P51 group -- Britain, China, France, Russia and the United States plus Germany -- also remains contested, with Iran speaking of five years and the West suggesting at least double that.

Some analysts have said the recent lack of clear progress and the far apart demands of the respective parties mean a comprehensive settlement by November 24 may already be out of reach.

"A full-fledged agreement is no longer possible before the deadline. What is still achievable is a breakthrough that could justify adding more time to the clock," Ali Vaez, senior Iran analyst at the International Crisis Group, told AFP on Monday.

"What is needed is a courageous political decision that neither side appears compelled to take until the eleventh hour," he said.

Iran and the US have said more time is not on the agenda, but the talks have already been extended once -- when a July 20 deadline was missed. Despite the logjam, neither side has indicated that it might walk away from the process.

The meetings in Muscat follow the revelation that Obama reportedly wrote to Iran's supreme leader Ayatollah Ali Khamenei to push for a deal, arguing that the Islamic republic and the West have shared regional interests.

IS link denied

This apparent reference to the fight against Islamic State group militants in Syria and Iraq was played down by Kerry, however, with the US diplomat saying in Beijing on Saturday "there is no linkage whatsoever" with the nuclear talks.

Domestic politics hang heavily over the process, given the loss in midterm elections of the Senate by Obama's Democrats to the Republican party, members of which have consistently bridled at the White House's negotiations with Iran.

If talks go sour in the coming weeks it is thought the US Congress may respond with fresh sanctions on Iran.

Obama has the power to veto them, but the prospect of new penalties could disrupt an already protracted process and push the negotiations towards being untenable for the Iranian government.

Zarif and President Hassan Rouhani are under pressure from lawmakers sceptical of the interim deal, which came into force in January, who have also said that a bigger, final agreement must be ratified by parliament.

As if to drive that message home on Sunday, 200 Iranian MPs signed a statement demanding that Zarif's negotiating team "vigorously defend" the country's nuclear rights and ensure a "total lifting of sanctions".