A final nuclear deal between Iran, the United States and its allies is unlikely to be solidified by the July 20 deadline, diplomats and analysts have told Reuters.
Western officials told Reuters an extension to the talks is inevitable.
"We're far apart," one diplomat said, adding that the talks would be "long and complicated."
The six-month interim deal reached in November to curb Iran’s nuclear program took effect in January. The agreement allows for a six-month extension.
President Obama would likely seek congressional consent to extend the talks, which would require a continuation in sanctions relief for Iran.
The next round of negotiations are scheduled for June 16-20 in Vienna. Diplomats reported snags in the talks held last month.
Iran said it wanted to maintain tens of thousands of enrichment centrifuges, well beyond what Western nations are willing to accept.
The P5+1 — the U.S., France, Russia, Great Britain, Germany and China — and Iran were expected to start drafting the final deal in May, but no full-scale drafting process began, Reuters reported.
An Iranian official said Iran is willing to extend the talks.
"We have to get rid of the sanctions immediately. Therefore, the talks will end, when this issue is totally resolved. A few more months will kill no one." Pushing the deadline to October would be fine, he said.
Another Iranian official close to President Hassan Rouhani’s government said they want the negotiations to succeed.
“Rouhani has put all his eggs in this basket. Failure of the talks means failure of reforms in Iran.”