Iran and Saudi Arabia, which recently decided to restore diplomatic ties in a China-brokered deal, have also agreed on several security issues including Riyadh's conditional support for Tehran's nuclear program and ending the war in Yemen, diplomatic sources said earlier this week.
The five agreed-upon items include some of the most intractable topics between the two Middle Eastern behemoths, whose rivalry has long played a destabilizing role in the region such as through their proxy war in Yemen.
The announcement on March 10 of the two countries' detente had only mentioned re-establishing ties that had been severed for seven years, and the latest revelation is the first on other agreements.
The agreement, crafted through secretive meetings between Chinese President Xi Jinping and Iranian and Saudi leaders, includes Riyadh's conditional support for a flagging international deal that limited Iran's nuclear ambitions, the sources told Kyodo News on Monday.
Saudi Arabia will politically support the restoration of the Joint Comprehensive Plan of Action, they said, referring to a 2015 agreement under which Iran curbed its nuclear program in exchange for sanctions relief from the United States, the European Union and the United Nations.
The JCPOA had been negotiated between Iran, the United States, Britain, France, Russia, China and Germany, but its implementation floundered after the U.S. unilaterally reneged on the agreement under former President Donald Trump in 2018.
Iran has consistently claimed that its nuclear development is peaceful, and not aimed at making nuclear weapons as feared by other countries.
Support from Saudi Arabia, which had agreed with the Trump administration's walk-out, could help lift the flagging nuclear deal.
Under another pledge, which if successful would reduce regional tensions, Iran will respect Saudi interests in the region and will support peace plans for the Yemen war, according to the sources.
A Saudi-led coalition has fought against Iranian-backed Houthi rebels since 2015, a year after the civil war was sparked.
Additionally, Shiite-majority Iran gave assurances that its ballistic missiles would not pose a threat to Saudi Arabia, the sources added.
The two rivals have said they will cooperate in conflict-ravaged Syria and Afghanistan, and Saudi Arabia has agreed to suspend support of anti-Iran media.
They have also agreed to cooperate with each other and follow common interests as members of the Organization of Petroleum Exporting Countries, the sources said, as well as commit to the security of maritime and energy tankers in the Persian Gulf, a strategic point for international energy transportation.
Saudi Arabia cut ties with Iran in 2016 after demonstrators attacked the Saudi Embassy in Tehran, following Riyadh's execution of a prominent Shiite cleric.
The two sides agreed earlier this month on normalizing diplomatic relations and announced reopening their respective embassies.