Iran said Monday any new talks with Saudi Arabia will depend on Riyadh's willingness to move ahead and be more "serious" to ease tensions after a five-year rift.

Shiite-majority Tehran and Sunni-kingpin Riyadh cut ties in 2016 after protesters attacked Saudi diplomatic missions in Iran, following Saudi's execution of a revered Shiite cleric.

The regional powers have been engaged in talks since April with the aim of improving ties, with four rounds of discussions taking place so far.

The talks were launched under Iran's former moderate president Hassan Rouhani, and have continued under his ultraconservative successor, Ebrahim Raisi.

"The discussions have not been cut off, but after the fourth round, no face-to-face talks have been held," Iranian foreign ministry spokesman Said Khatibzadeh said Monday.

"Progress hinges on Riyadh showing a serious willingness to move forward, and avoid media rhetoric," he told a news conference.

"If we see that the other side is serious, then a new round of talks will take place," he added.

The last round of talks took place in September, Saudi Prince Foreign Minister Faisal bin Farhan has said.

Iranian Foreign Minister Hossein Amir-Abdollahian said in October that the talks were "on the right track".

The two countries are at odds over several regional issues, including the Yemen war and the conflict in Syria and Lebanon, where they back opposing sides.