FRANKFURT, Jan 17 (Reuters) - Australian miner Fortescue Metals" (FMG.AX) newly-announced deal to supply green hydrogen to Germany is just the start as the rest of the world will catch up with Europe"s lead, Fortescue"s chairman told a Berlin industry conference on Monday. European policymakers and industry have been embracing hydrogen as a way to meet an EU goal for net zero emissions by 2050, but critics say it serves to prolong the use of fossil fuels when the aim should be to get rid of them entirely and it requires large amounts of energy to produce. Green hydrogen has the best environmental credentials of the various shades of the clean-burning fuel because it is produced by using renewable energy to electrolyse water, rather than relying on carbon-based fuel. Under the German deal announced on Sunday, Fortescue"s green power arm, Fortescue Future Industries (FFI), will supply up to 100,000 tonnes a year of hydrogen from 2024 to German chemical maker Covestro (1COV.DE). read more "The big customers will be initially European, (South) Korean and Japanese and the big producers will be Latin America, Australia, Australia-Pacific and then Africa," Fortescue"s chairman and biggest shareholder Andrew Forrest told the annual Handelsblatt Energy Summit 2022. "I really see huge potential. It will be those countries which have the best leadership because renewable energy is everywhere," he added. A specialised trial vessel to carry hydrogen was being tested and more ships could be ready for the bulk shipping of hydrogen by 2023, Forrest said. read more He said he believed that by around 2025, hydrogen would start being widely used to replace oil, coal and gas and by industry, such as steelmaking. Fortescue, the world"s No. 4 producer of iron ore, used to make steel, is seeking to transform itself into a green energy company.