Energy executives warn that readily available oil stocks are shrinking, VnExpress reports from the Energy Intelligence forum in London. Saudi Aramco chief Amin Nasser estimated commercial inventories at below six billion barrels, with much of that oil unavailable for immediate release because of operational constraints and reserve requirements. Speakers said energy-market pressures could persist into 2027. These are industry leaders' estimates and risk assessments, rather than an independently audited inventory of all the world's oil reserves.