This handout picture provided by the Iranian presidency on April 14, 2021, shows President Hassan Rouhani speaking during a cabinet meeting in the capital Tehran. (IRANIAN PRESIDENCY / AFP)

TEHRAN - Iranian President Hassan Rouhani said on Wednesday that the main issues between Tehran and Washington in the ongoing nuclear talks in Vienna have been settled, official IRNA news agency reported.

"Today, we are witnessing the resolution of major issues with the United States" in the Vienna talks aimed at the revival of the 2015 nuclear deal, formally known as the Joint Comprehensive Plan of Action (JCPOA), Rouhani said at the cabinet meeting.

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Major economic projects inaugurated recently and to be opened in the near future in Iran are the "signals" that anti-Iran economic pressures of former US president Donald Trump have failed, the Iranian president noted.

He hailed what he called the "victory" of his administration in the face of challenges caused by the United States, linking them to the patience of the Iranian people, his administration's prudence and leadership guidance.

Iranian Deputy Foreign Minister and top nuclear negotiator Abbas Araqchi said in a statement on Telegram that diplomats from China, Russia and the European Union will hold a meeting of the accord’s Joint Commission in Vienna on Wednesday before returning to their capital cities to consult with their governments over remaining sticking points.

Major economic projects inaugurated recently and to be opened in the near future in Iran are the "signals" that anti-Iran economic pressures of former US president Donald Trump have failed.

Hassan Rouhani, Iranian president

Sounding a note of optimism, Araghchi said differences between participating countries “have reached a point where everyone believes that they’re not unsolvable,” according to comments he made to Iranian state TV.

He added that diplomats will agree on a date to return to the Austrian capital for the next round of talks at the end of Wednesday’s meetings. “All the delegations are determined and there is full seriousness,” Araghchi said.

The nuclear deal has been on the verge of collapse since it was abandoned by former US president Donald Trump in 2018. His sanctions on Iran’s economy, and the Islamic Republic’s subsequent decision to significantly expand its nuclear program, triggered a crisis in the Persian Gulf which has roiled markets and almost led to war.

Oil market participants are closely watching the talks for signs of when the US will ease its sanctions on Iran’s energy sector and allow the Islamic Republic to return to global oil markets and hike crude production back up to pre-sanctions levels.

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Crude prices rose above US$70 a barrel on Tuesday as traders reacted to signals that the talks were stalling and would need to go to another round. Brent climbed another 0.9 percent to US$70.88 at 10:30 am in London on Wednesday.

Ali Rabiei, Iran’s government spokesman, said this week officials hope they can have the nuclear deal fully back in effect by August, when president Rouhani leaves office, revising expectations that an agreement would be reached this month before the country’s presidential election on June 18.