Iranian President Hassan Rouhani said in an interview Sunday that he is ready to discuss a "plan of action" for Syria's post-war future after the Islamic State group is defeated.

"That is not a problem for us from right now, to start holding discussions and dialogues so as to determine and reach the conclusion of the next plan of action after the terrorists are driven out that territory," Rouhani said in an interview to NPR radio.

"But we must all act in unison and have a formula that is required to drive out the terrorists, immediately."

Iran, which along with Russia is allied with President Bashar al-Assad in the war, has until now been kept out of UN diplomatic efforts to piece together a political solution for Syria.