Japan has secured a tentative agreement with Australia to buy rare earths, key minerals used in the manufacturing of electronic products from car batteries to military equipment, in a strategic move to cut its dependence on China, the world’s dominant producer. Sojitz, a Japanese trading company and the country’s largest importer of rare earths, said on Wednesday it had entered a “strategic alliance” with Lynas, an Australian-listed group that owns one of the world’s richest rare earth deposits. The groups were “investigating a long-term supply agreement”, Sojitz said. The announcement came a day after Kevin Rudd, Australia’s foreign minister, told his Japanese counterpart, Seiji Maehara, in Canberra that Australia would be a long-term supplier of rare earths to countries such as Japan. Lynas shares jumped 10.5 per cent to A$1.53, while shares in Sojitz rose 9 per cent to Y168. Under the agreement, Sojitz said it would seek funding from the Japan Oil, Gas and Metals National Corporation, a state-affiliated investment body, to help pay for a $250m expansion of Lynas’ Mount Weld rare earth mine in western Australia. Sojitz said it was seeking 9,000 tonnes of rare earths a year from Lynas during the next 10 years.