Australia’s two largest automotive retail chains, Supercheap Auto and Autobarn, are running out of tubs of the diesel exhaust fluid AdBlue as small-business truck operators, trades people and owners of diesel passenger vehicles race to secure dwindling supplies.

Supercheap Auto, which runs more than 300 stores selling automotive parts and accessories, has brought in customer limits of 20 litres per customer for stores that still have stock, usually sold in 10-litre tubs. Shoppers are only allowed to purchase in-store.