Australia would consult with Iran over possible plans to expand RAAF air strikes to Syria, underscoring Foreign Affairs Minister Julie Bishop's push for more co-ordination with the Shiite regional power in the fight against Islamic State.

Ms Bishop told Fairfax Media on Wednesday that Iran would be one of a number of countries Australia would talk to if it decides to accept the formal request from Washington to expand air strikes from Iraq to more dangerous neighbour Syria.

Such talks are politically complex and sensitive, however. While Shiite Iran is a powerful force in fighting the Sunni extremist group, it has barely shrugged off its long-held international status as a rogue nation.