China's CMRG has reportedly told some steel mills to stop talks with Rio Tinto (RIO LN) fro shipments from September, according to sources

This follows the established pattern of China Mineral Resources Group, the state-backed centralised iron ore buyer, pressing the majors on pricing terms by instructing mills to halt purchases from individual producers, a tactic previously directed at another large Australian miner before being extended across the complex. The mechanism runs through seaborne iron ore rather than steel output itself: cargoes from the targeted producer reprice or get deferred, while rival supply and portside inventories absorb displaced demand, so the spread between the targeted miner's product and the benchmark, and between paper and physical, is where pressure typically shows first. Past episodes of this kind have tended to be negotiating leverage rather than a durable embargo, with flows resuming once terms are struck, though the escalation from one producer to two raises the probability this is a broader push on the annual pricing framework rather than a bilateral dispute. Worth noting is that the mills retain latitude on existing stockpiles and non-targeted seaborne supply, which historically blunts the volume effect on spot. The follow-ons are confirmation from other mills, any counterparty comment from Rio Tinto, and whether freight rates and the Singapore futures curve reflect cargo diversion. Chinese port inventory behaviour is the tell on duration.