The fourth round of negotiations of the parties concerned with the Iranian nuclear deal will be held today in Vienna, amid cautious optimism that an agreement will be reached before mid-June, while Tehran warned against turning the negotiations into a process of attrition.

Indirect negotiations began at the beginning of last April in the Austrian capital Vienna between the United States and Iran, with the Europeans and the rest of the signatories of the 2015 agreement, with the aim of preventing Tehran from developing a nuclear weapon.

The chief Iranian negotiator, Abbas Araghchi, confirmed that Tehran would continue the path of negotiations, stressing that his country's priority is accuracy, not time.

He explained that the sticking points in the negotiations are serious and fundamental, warning that the talks will not turn into what he described as a draining process.

The essence of the nuclear deal is for Iran to commit to taking steps to restrict its nuclear program, making it difficult for it to obtain fissile material for a nuclear weapon in exchange for relief from US and European sanctions, and those imposed by the United Nations.

Tehran denies it is seeking nuclear weapons.

The Iranian negotiating team led by Araghchi arrived in Vienna earlier and held talks with the Director General of the International Atomic Energy Agency, Rafael Grossi.

In statements to Iranian media, after his meeting with Grossi, Araghchi said that there is a good understanding between Iran and the International Atomic Energy Agency on various thorny issues.

He added that the two parties have deep cooperation, including even the issue of the expiry of the additional protocol between the agency and Iran.

It should be noted that this protocol stipulates, among its provisions, the installation of surveillance cameras at nuclear sites, and the right of IAEA inspectors to visit nuclear sites.

The additional protocol expires on May 21, which poses a problem if no agreement is reached before this date.

Final round?

Russia's permanent representative to international organizations in Vienna, Mikhail Ulyanov, said that the next and possibly final round of Vienna talks on re-implementing the joint work plan on the Iranian nuclear file will begin on Friday.

Ulyanov added, in a tweet, that if the need arose, negotiators might decide to take a new break to obtain more instructions from their capitals.

Improve agreement

On the other hand, a US State Department official announced that Washington wants to talk with Iran about improving the nuclear deal after reaching understandings on it, adding that it understands what Iran must do to comply with the agreement and also knows what it must do as well.

He emphasized that he does not intend to invent a new nuclear agreement, but rather to comply with the 2015 agreement.

The US official expressed his country's readiness for the scenario of Iran not returning to the nuclear agreement, stressing that Washington does not want that to happen, he said.

He added that the previous US administration tried to pressure Iran for years, but this strategy did not succeed.

He pointed out that the last three rounds clarified more steps that should be taken to return to the nuclear agreement.

He pointed out that Washington had raised the issue of the Americans detained in Iran, but no agreement had been reached on them.

Yesterday, American, Iranian and European officials said that gaps remained wide between Washington and Tehran regarding the resumption of compliance with the Iran nuclear agreement signed in 2015, despite a US official saying that an agreement is possible within weeks if Iran takes a political decision to do so.

"Is it possible to see a joint return to compliance with the nuclear agreement in the coming weeks or an understanding on mutual compliance? The answer is yes, it is possible," the official told reporters in a telephone briefing, asking not to be named.

In an interview with NBC television, US Secretary of State Anthony Blinken said that Washington does not know whether Iran is ready to take the decisions required to return to compliance with the agreement.

An American proposal

A European diplomat said Washington had put forward a comprehensive proposal that included lifting sanctions on key sectors such as oil and gas and banking, and hinted at a measure of openness to easing sanctions related to terrorism and human rights.

The diplomat, who asked not to be named, added that Iran had shown no desire to curtail or destroy any experience it might have gained from working on advanced centrifuges.

A US official said that it is possible to revive the nuclear deal before the Iranian elections scheduled for June 18, but it falls again on Iran to make such a political decision.

The official added that it requires Iran to stop asking Washington to do more than what is included in the agreement, while Tehran seeks to do less.