World powers have failed to temporarily control Iran's nuclear programme after France objected that proposals did not go far enough.
French foreign minister Laurent Fabius said that the talks managed to narrow differences without eliminating them, adding that there are 'still questions to be dealt with' in future rounds.
Fabius said there was disagreement over efforts to limit Iran's uranium enrichment to levels that would require substantial further enriching before they could be used as the fissile core of a nuclear weapon.
Secretary of State John Kerry said that significant progress had however been made on the differences that remain.
According to Fox News, a Western diplomat said a new round would be needed to agree on all points of a temporary deal to ensure that Tehran's nuclear programme remains peaceful.
European Union foreign policy chief Catherine Ashton, who coordinated the talks, said Iran and the five permanent U.N. Security Council members plus Germany would meet again on November 20, the report said.
According to the report, Kerry and counterparts from Britain, France and Germany discussed how to resolve the obstacles, including differences on ways to reduce Tehran's ability to make atomic weapons using plutonium and enriched uranium.
Among the terms to which Iran would purportedly have to agree are: to stop enriching nuclear fuel to the 20 percent purity; render unusable most of its stockpile of such fuel; not to use advanced IR-2 centrifuges, which can enrich nuclear fuel five times faster than older centrifuges and not to activate a plutonium reactor at Arak, the report said.
In turn, the super powers, including Russia and China, would unfreeze some Iranian assets held in banks overseas and consider easing sanctions banning trade in gold, precious metals and petrochemicals, the report added.
