Lynas Rare Earths boss Amanda Lacaze says she is disappointed with a Malaysian government decision that threatens to disrupt the company’s ability to produce and supply critical rare earth minerals, and will appeal against a ruling that has put Australia at odds with its South-East Asian neighbour.

Malaysia’s Atomic Energy Licensing Board has confirmed it will ban Lynas cracking and leaching rare earths on its shores from July 1, despite lobbying from Australia, the US, Japan and the European Union to give the company more leeway.