US Under Secretary of State for Political Affairs Wendy Sherman said it was Iran that would need to shift its position: "What is still unclear is if Iran is really ready and willing to take all the necessary steps to assure the world that its nuclear program is and will remain exclusively peaceful."
Iranian Foreign Minister Mohammad Javad Zarif highlighted the wide gulf between the sides, urging the six nations to "abandon excessive demands which will not be accepted by Iran."
"Still we have not overcome disputes about major issues," he told reporters as five days of negotiations in Vienna wound up. "There has been progress, but major disputes remain." — Source