South Pars

South Pars is Iran's share of the world's largest natural gas field, a subsurface reservoir straddling the maritime boundary with Qatar, whose half is called North Dome. Discovered by NIOC in 1990 with first gas produced in 2002, the field runs 24 operational phases processed onshore at Asaluyeh in Bushehr Province and supplies roughly 70–80% of Iran's National Gas production, with combined Iran-Qatar reserves estimated at 1,800 trillion cubic feet, the largest gas accumulation on Earth.

Total led early development but withdrew after the 2018 US JCPOA exit; CNPC took over before exiting in 2019, and Petropars completed Phase 11 independently in 2023, Iran's first fully domestic deepwater development, reaching record output of 730 million cubic metres a day in 2025. Because the reservoir is continuous, extraction on the Iranian side propagates pressure to Qatar's North Dome half: the two states cannot fully decouple economically even where they are diplomatically estranged, since drawdown decisions on one side affect recoverable volumes on the other. The combined field underpins 20–25% of global LNG exports, giving South Pars weight in European and Asian gas markets FAR beyond its role inside Iran.

That structural interdependence has repeatedly shaped regional diplomacy: Qatar's occasional role as a back-channel between Washington and Tehran sits awkwardly alongside its permanent stake in the reservoir Iran calls South Pars, since Doha has as much to lose from damage on the Iranian side as Iran does. Israeli strikes on South Pars infrastructure, most recently hitting the Asaluyeh petrochemical complex on 6 April 2026, have targeted onshore processing rather than the reservoir itself, since surface damage strands the gas without touching the field. Iran's petrochemical exports earned roughly $14 billion annually before the war, a hard-currency stream that compressed sharply during weeks of bombing.