Iranian President Ebrahim Raisi said on Thursday that Tehran would not back down from any of its red lines in the Vienna talks aimed at reviving the 2015 nuclear deal, while blaming Washington for the "complexity" of the talks.
Raisi added - in a tweet on Twitter - "The government is actively seeking to lift the sanctions in the Vienna talks."
Earlier on Thursday, the Secretary of Iran's Supreme National Security Council, Ali Shamkhani, said that the United States had no will to reach an agreement on reviving the nuclear deal during talks in Vienna, as it insisted on "unacceptable proposals."
Shamkhani added - in a tweet on Twitter - that Washington's delay in making the political decision will make the talks more complicated by the hour.
He stressed that the United States has no will to reach an airtight agreement, adding that it presents "unacceptable proposals and insists on a quick agreement on false pretexts." He did not go into details of the American proposals.
In turn, the website "nournews" of the highest Iranian security body confirmed that the revival of the nuclear agreement cannot restrict Tehran's pursuit of its missile and space programs.
The site added - in a tweet on Twitter - that Iran is not ready to negotiate its defense capabilities and regional policies.
Iran is also demanding clear guarantees that no future US president will ever again abandon the nuclear deal.
The semi-official Tasnim news agency quoted an unnamed source as saying that negotiators in Vienna are still trying to address some major issues.
The Vienna talks aim to restore the United States to the agreement, especially by lifting sanctions, and Tehran's compliance again with all of its obligations under its provisions.
European negotiators from France, Britain and Germany have temporarily left the talks, because they believe they have reached the maximum point they can reach in the negotiations and that it is now up to the United States and Iran to agree on the outstanding issues.
Negotiations have recently reached critical stages, with various parties confirming progress, but with sticking points remaining.
However, Russia's new position has cast a shadow over the talks for days.
Foreign Minister Sergey Lavrov revealed that his country stipulated, before supporting any understanding, obtaining written guarantees from the United States that Western sanctions recently imposed on Moscow against the backdrop of its invasion of Ukraine, will not affect its cooperation with Tehran in the economic and military fields.
Washington considered that Russia's position was "out of context" on the issue, as there was no link between the new sanctions and cooperation within the framework of the nuclear agreement, while Paris expressed its "concern" that the new demands would cause an additional delay in the completion of the agreement.