Saudi Arabia, which backs Syrian armed mercenaries on ground, rejected on Monday Iran’s participation in the Geneva-II peace talks unless Tehran backs efforts for a transitional government in war-torn Syria.

Saudi Arabia, which backs Syrian armed mercenaries on ground, rejected on Monday Iran's participation in the Geneva-II peace talks unless Tehran backs efforts for a transitional government in war-torn Syria.

Iran did not "announce officially and openly its agreement (to)... the creation of a transitional government," said a Saudi official statement.

This ... renders the Islamic Republic "unqualified to attend" the international peace conference on Syria that opens Wednesday in Switzerland, it added.

UN Secretary General Ban Ki-moon sparked a furore Sunday by inviting Iran to the talks.

Ban's invitation came after Tehran vowed to play a "very positive and constructive role" in efforts to end Syria's three-year civil war.

Iran said Monday that it will attend the peace talks but without preconditions.

Washington, London and Paris reacted immediately, saying Iran would have to clearly and publicly support the idea of a Syrian transitional government if it wanted to attend.

The Saudi statement said of this week's conference that "its main role is to implement Geneva-I."

Regional powerhouse Saudi Arabia and other Arab states of the Gulf have repeatedly voiced support for rebels fighting Assad's regime.

Saudi Arabia's intelligence chief Bandar bin Sultan told Russian President Vladimir Putin last month that Riyadh would send a delegation to the meeting, but only on the condition the opposition is represented by its Saudi-backed National Coalition.

Riyadh shocked the international community by announcing on October 18 that it would not take up a seat it was awarded at the UN Security Council, citing the council's failure to act on the Syria conflict.