Chief Iranian nuclear negotiator Ali Bagheri-Kani held talks with Oman’s Undersecretary for Diplomatic Affairs Khalifa al-Harthy at the Ministry of Foreign Affairs in Muscat on Thursday.
The Omani Foreign Ministry said in a statement that the talks addressed the bilateral ties and ways to enhance cooperation between their countries to serve their interests.
"A number of regional and international issues of common concern were also discussed," it added.
Iranian ambassador to Oman Ali Najafi attended the officials' talks, reported the IRNA news agency.
Oman is trying to revitalize its mediation role between Washington and Tehran, especially after negotiations aimed at reviving the 2015 nuclear deal failed in September amid mutual accusations of unreasonable demands.
Muscat previously hosted rounds of indirect talks between US National Security Council official Brett McGurk and Bagheri-Kani, a Western official told Reuters in mid-June.
Iranian and Western officials said the two parties want to sketch out steps to limit the Iranian nuclear program, release some detained US citizens held by Iran and unfreeze some Iranian assets abroad.
Iranian officials said the talks under Oman’s mediation increase the possibility of freeing US detainees in exchange for releasing frozen Iranian assets in South Korea, Iraq, and the World Bank.
Last Saturday, Iran's government submitted a bill to parliament to approve sending the case of frozen assets in South Korean banks to arbitration.
The government then submitted a complaint at international courts against Seoul regarding Tehran's assets that have been frozen due to US sanctions.
In June, Bagheri-Kani visited Abu Dhabi, where he met his counterpart from the European Troika. He later held talks with the European Union's coordinator for nuclear negotiations with Iran, Enrique Mora.
In both meetings, the Iranians received a warning from the Europeans about maintaining the nuclear missile sanctions set to expire on October 18 under the 2015 nuclear deal.
Meanwhile, Iraqi Prime Minister, Mohammad Shia al-Sudani, announced that a delegation from the Iraqi central bank and the Trade Bank of Iraq (TBI) traveled to Oman to agree on a formula for transferring the funds to the Sultanate, in agreement with the US treasury.
"Work is continuing with the US regarding the unpaid bills, which dropped to 9.25 billion euros," Sudani told reporters in a press conference in Baghdad, adding that Iraq has transferred around 1.9 billion euros owed to Iran within the first seven months of his government based on a mechanism agreed upon with Washington.
The US State Department spokesman Matthew Miller said during a press conference that the waiver provided to Iraq last month allows for the transfer of funds from Iran's restricted accounts in Iraq to banned accounts in select third-country banks.
Miller added that Sudani "has demonstrated commitment to strengthening Iraq's energy security, and this mechanism is only one way we seek to alleviate Iranian pressure on Iraq."
"We work closely with Iraq to ensure these energy payments are managed in a manner consistent with US sanctions and cannot be diverted for illicit means," noted the spokesman, adding that the US remains "supportive of transactions for humanitarian goods and will continue to engage with the Iraqi Government on these complex issues."