High power prices could force the closure of a major fertiliser plant employing about 500 workers in north-west Queensland unless a buyer can be found in what would be another blow to the Albanese government’s plans to revive manufacturing on the east coast.

Dyno Nobel chief executive Mauro Neves said the company’s Phosphate Hill plant 140 kilometres from Mount Isa was at risk of closure due to high gas prices driving up the costs of the energy-intensive process of making the fertiliser that is commonly used for food crops across the country.