Regional rivals Saudi Arabia and Iran are coming to an OPEC oil ministers' conference with competing agendas.
Iran could use Wednesday's meeting as the launching pad for where it hopes to be in six months — free of sanctions that are choking its oil exports and ready to weaken Saudi authority by reasserting itself as a top OPEC force.
Before the oil sanctions started biting last year, Iran was second only to the Saudis in OPEC oil production, pumping around 2.7 million barrels a day. Output has dropped by nearly a third since.
Iran hopes to reach a final nuclear accord by mid-2014 that grants it full sanctions relief. Tehran is expected to lobby at Wednesday's meeting for a greater share of total OPEC output come next year.