Muslim Shiite-majority Iran and Sunni power Saudi Arabia, on opposing sides in multiple Middle East conflicts, have been engaged in talks since April at the highest level since cutting ties in 2016.

The discussions, hosted by Iraq as it seeks to act as a regional mediator, were launched under Iran's former, moderate president Hassan Rouhani, who was replaced in August by Raisi.

The talks have led to "serious progress" regarding Gulf security, Tehran's foreign ministry spokesperson Saeed Khatibzadeh said on September 23.

The latest round of talks was confirmed by three Iraqi sources, all speaking on condition they not be named.

"An Iranian official met with a Saudi official in Baghdad, following previous meetings between the two countries," one source told AFP, confirming the talks took place in recent days.

A government official and a source close to the government confirmed the meeting, without providing more details.

US ally Saudi Arabia and Washington's arch-foe Iran are at odds over many regional issues, including the wars in Yemen and Syria.

Riyadh also has concerns about Iran's nuclear programme, despite the Islamic republic's insistence it is pursuing only "peaceful" nuclear technology.

Saudi King Salman said in his recent speech by video conference to the UN General Assembly that "we hope that our talks will lead to tangible results that would build trust" and revive bilateral "cooperation".

He again called on Tehran to "cease all forms of support" for armed groups in the region and reaffirmed the kingdom's support for "international efforts to prevent Iran from acquiring nuclear weapons".