U.S. Secretary of State John Kerry arrived late Friday in Vienna seeking to wrap up a deal with Iran by a quickly approaching deadline.
Kerry was expected to meet Iranian Foreign Minister Mohammad Javad Zarif on Saturday, three days before the Tuesday deadline for a deal that officials warn may be missed by a few days, according to AFP.
France's Foreign Minister Laurent Fabius and other foreign ministers were due to arrive over the weekend for the talks, the report noted.
Kerry’s arrival coincided with comments by a senior Western diplomat, who said earlier Friday that major differences remain between Iran and world powers on several key issues.
"The questions of access and transparency, PMD (possible military dimensions) and sanctions remain extremely problematic," the diplomat said. "We can find an agreement on some points, but on major issues there are still big differences."
Those comments were echoed by Iranian Deputy Foreign Minister Abbas Araqchi, who told state television earlier, "Some major problems exist which are still blocking the work… but in other areas we have made good progress."
"Overall, the work is moving ahead slowly and with difficulty," he added, according to AFP.
The P5+1 — the United States, China, Russia, Britain, France and Germany — want Iran to curtail its nuclear activities in order to make any push to make nuclear weapons all but impossible.
The deal, it is hoped, would end to a standoff dating back to 2002 that has threatened to escalate into armed conflict and poisoned the Islamic republic's relations with the international community.
In return for downsizing its activities and allowing closer UN inspections, Iran, which denies wanting nuclear weapons, would see painful UN and Western sanctions that have choked its economy lifted.
There have been several indications from officials in recent weeks that the talks were stalled. Two diplomats said a week ago that the sides are still apart on all main elements of the nuclear deal. Previously, a diplomat who had spoken with a Russian news agency said the talks are “virtually stalled”.
To make matters worse, on Tuesday Iran's supreme leader, Ayatollah Ali Khamenei, set out key "red lines" for the final agreement which appeared to go against parts of what had been agreed upon in an interim deal in April.
Khamenei said that all economic and financial sanctions imposed by the UN Security Council and the United States must be lifted on the same day that an agreement is signed.
In addition Khamenei took issue with the International Atomic Energy Agency (IAEA) visiting military sites vital for a UN probe into allegations of past efforts to develop nuclear weapons.
Nevertheless, Kerry earlier this week appeared unfazed by Khamenei’s remarks, saying they were meant for “domestic political consumption”.
(Arutz Sheva’s North American desk is keeping you updated until the start of Shabbat in New York. The time posted automatically on all Arutz Sheva articles, however, is Israeli time.)