Iran's nuclear negotiators return to Tehran from Vienna after days of indirect talks on reviving a 2015 deal with Washington and other world powers.

Iran says the IAEA should
Iran says the IAEA should "completely" resolve the issues related to questions over nuclear material at its undeclared sites. (Reuters)

Iran has said it is examining a "final text" presented by the European Union at the negotiations in Vienna aimed at restoring a 2015 nuclear deal between Tehran and world powers.

"As soon as we received these ideas, we conveyed our initial response and considerations... but naturally, these items require a comprehensive review, and we will convey our additional views and considerations", state news agency IRNA quoted an unnamed foreign ministry official as saying on Monday.

The comments came after a European official, speaking on condition of anonymity, said the EU has tabled the "final" version of the text, negotiations are finished, "and it will not be renegotiated."

Talks aimed at reviving the agreement over Iran's nuclear programme resumed on Thursday in Vienna, months after they had stalled.

Iranian sources have suggested an International Atomic Energy Agency probe is a key sticking point in reviving the nuclear deal known as the Joint Comprehensive Plan of Action (JCPOA).

But the European official said: "That has nothing to do with" the JCPOA.

Iran on Sunday said the IAEA should "completely" resolve the issues related to questions over nuclear material at its undeclared sites.

READ MORE: What are the hurdles in the way of Iran nuclear deal?

'Relative progress' is made

The IAEA's board of governors adopted a resolution in June, censuring Iran for failing to adequately explain the discovery of traces of enriched uranium at three previously undeclared sites.

The Iranian foreign ministry official added on Monday that, during the talks of the past few days, "we shared our positions with the other sides, and relative progress was made in some issues."

He added that the negotiating team looks to "protecting the rights and interests of the Iranian nation" as well as "ensuring the benefits and guaranteeing the sustainable implementation of the other party's obligations and preventing the repetition of US illegal behaviour".

The negotiations to revive the deal began in April 2021 before coming to a standstill in March.

The 2015 agreement gave Iran sanctions relief in exchange for curbs on its nuclear programme to guarantee that Tehran could not develop a nuclear weapon - something it has always denied wanting to do.

But the US unilateral withdrawal from the accord in 2018 and the reimposition of biting economic sanctions prompted Iran to begin rolling back on its own commitments.

READ MORE: Iran sanctions dozens of Americans as nuclear talks hit deadlock

Source: TRTWorld and agencies