The general chief of staff of Saudi Arabia's armed forces, Fayyad al-Ruwaili, met his Iranian counterpart, Mohammad Baqeri, in Tehran during a rare visit on November 10.
Iran's official IRNA news agency said they discussed the development of defense diplomacy and bilateral cooperation without offering any details.
Iranian media said Baqeri had discussed regional developments and defense cooperation with Saudi Defense Minister Prince Khalid bin Salman al-Saud last year.
Ruwaili is only the second high-profile Saudi official to travel to Tehran since Iran and Saudi Arabia agreed to restore diplomatic relations after seven years following Chinese-brokered talks in March 2023. Previously, Foreign Minister Faisal bin Farhan visited Iran in June 2023.
Sunni-majority Saudi Arabia severed ties with Shi'a-dominated Iran in 2016 after its diplomatic compounds in Tehran and Mashhad were attacked by protesters over Riyadh's execution of Shi'ite cleric Nimr al-Nimr.
The trip comes days after the election of Donald Trump, whose second term as U.S. president begins in January. He has pledged to bring peace to the Middle East, where U.S. ally Israel is engaged in wars against Iranian-backed groups in Gaza and Lebanon.
Hamidreza Azizi, a fellow at the German Institute for International and Security Affairs, said the timing of the trip was significant because it comes as various countries are preparing for a second Trump presidency.
He said the Saudis' decision to send their top military official to Tehran "is a signal that they are committed" to the detente process that started last year and that "they don't want Trump's election to jeopardize the recently improving relations with Iran."
Separately, Iranian President Masud Pezeshkian spoke with Saudi Crown Prince Muhammad bin Salman on the phone and discussed expanding bilateral relations, according to Pezeshkian's office.
Trump had good relations with Persian Gulf Arab states in his first tenure in office and worked on normalizing relations between Arab states and Iran's archfoe, Israel.
Saudi Arabia has not normalized relations with Israel but Trump's son-in-law, Jared Kushner, is said to have discussed the possibility of normalization with Saudi Arabia since 2021.
In another sign of warming relations, Saudi Arabia announced last month that it held military drills with Iran in the Sea of Oman.
By RFE/RL