The Biden administration has resumed informal talks with Iran in an effort to secure the release of US prisoners in Tehran and to curtail the country's expanding nuclear program, according to people familiar with the conversations, a report published by the Wall Street Journal (WSJ) on Wednesday noted. 

As talks resumed, Washington accepted €2.5 billion, or $2.7 billion, in payments by the Iraqi government for Iranian electricity and gas imports, according to US and Iraqi officials.

Baghdad announced that the amount belonging to Iran and previously frozen under US sanctions were released, the head of the Iran-Iraq Joint Chamber of Commerce Yahya Ale Eshaq told the Tasnim News Agency. Economic sanctions imposed by the United States had frozen the funds.

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The transfer of these amounts was portrayed by US authorities as normal and unrelated to the conversations. Similar money has been released in the past, but this time in euros rather than local currencies, according to the WSJ. 

Since negotiations between senior US and Iranian officials began in New York in December, White House officials have been to Oman at least three times for further indirect encounters, while Omani officials relayed signals between the two countries.

US treaty to limit Iranian nuclear development

President Biden promised to revive the JCPOA, which was to limit Iran's nuclear development in exchange for the easing of economic sanctions. The US had withdrawn from the agreement under former President Donald Trump.

In exchange for the release of prisoners and restrictions on nuclear development, Tehran is asking billions of euros in Iranian energy money that has been frozen abroad due to US sanctions. Iranian officials have frequently linked the prospective release of detainees to gaining access to $7 billion in Iranian cash kept in South Korea, as well as billions more dollars held in Iraq for gas and oil exports.

Former South Korean government officials with knowledge of the situation claimed talks are ongoing with Iran and the United States to release the funds for humanitarian causes.

Western calls for Iran to 'de-escalate' 

Since the United States reimposed sanctions in 2018, Iran has developed its nuclear program and has been accumulating 60%-enriched uranium for more than two years, according to the WSJ, making it the only non-nuclear-weapons state to do so, adding that those involved with the negotiations believe that the West is calling for Iran to take de-escalation moves such as pausing the accumulation of 60%-enriched material. 

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With regard to US terms, if tensions can be reduced during the summer, it may lead to larger talks, possibly even a reopening of talks on the 2015 nuclear deal, according to the WSJ. 

Oman: A mediator 

Omani officials shuttled messages between the White House's Middle East senior advisor Brett McGurk and Iran's chief nuclear negotiator, Ali Bagheri Kani, in so-called proximity talks in the Omani capital Muscat in February, March, and May, according to people involved in or briefed on the negotiations. 

McGurk also visited Oman in late May, soon before Omani ruler Sultan Haitham bin Tarik flew to Tehran to see the Iranian leader Seyyed Ali Khamenei. Bagheri Kani was present at the Iran-Oman meeting on May 28. Last week, Axios reported on the May proximity discussions in Oman.

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According to the outlet, the two US advisors flew to "Israel" to allegedly brief Israeli Prime Minister Benjamin Netanyahu on US talks in Saudi Arabia.

This was significant because previously, the Biden administration expressed grave concern regarding Iranian advances in the nuclear program, which the US alleged could be a cause for regional military escalations.