Iran on Thursday welcomed a "change of tone" from Saudi Arabia that could clear the way to a new era of cooperation between the rival regional powers.  

The Islamic republic has been "a pioneer on the path to regional cooperation and welcomes the change of tone from Saudi Arabia," said Iranian Foreign Ministry spokesperson Saeed Khatibzadeh.

Saudi Crown Prince Mohammed bin Salman called Tuesday in a television interview for "a good and special relationship" with Tehran, after sources said the two countries had held secret talks in Baghdad.

Khatibzadeh, in a statement, said that "by adopting constructive stances ... the two countries ... can enter a new chapter of interaction and cooperation to reach peace, stability and regional development, by overcoming differences."

The neighboring countries, locked in a fierce struggle for regional dominance, cut ties in 2016 after Iranian protesters attacked Saudi diplomatic missions following the kingdom's execution of a revered Shiite cleric. The Saudi crown prince has previously lashed out at Tehran, accusing it of fueling regional insecurity. 

The talks in Baghdad, facilitated by Iraqi Prime Minister Mustafa al-Kadhemi, remained secret until the Financial Times reported that a first meeting was held on April 9. An Iraqi government official confirmed the talks to AFP, while a Western diplomat said he had been "briefed in advance" about the effort to "broker a better relationship and decrease tensions."

Riyadh has officially denied the talks in its state-backed media, while Tehran has stayed mum, asserting it has "always welcomed" dialogue with Saudi Arabia.

The initiative comes at a time of shifting power dynamics, as U.S. President Joe Biden seeks to revive the tattered 2015 nuclear deal that was abandoned by his predecessor Donald Trump.

Saudi Arabia and Iran have backed opposite sides of several regional conflicts, from Syria to Yemen, where a Saudi-led coalition is fighting the Houthi rebels. Iran supports the Houthi rebels, who are battling the Saudi-led military coalition that intervened in Yemen's war in 2015.

In comments broadcast late on Tuesday, Crown Prince Mohammed said Riyadh still had problems with Iran's "negative behavior," mentioning Tehran's nuclear program, missiles and support for proxies around the region.

But he added: "We are working with our regional and global partners to find solutions to these problems and we hope to overcome them for good relations that benefit everyone."

Ending a regional tour on Thursday, Iranian Foreign Minister Mohammad Javad Zarif said in a tweet that there were "Indications of positive signs on horizon."

(With input from AFP, Reuters)