Fortescue said on Wednesday it has signed a $2.8 billion partnership with German-Swiss equipment manufacturer Liebherr to create one of the world's largest zero-emission mining fleets.

The two companies had initially signed the deal to develop green technology-based trucks to haul iron ore out of Fortescue's mines in 2022 and have now agreed to increase the mining fleet - to be supplied by Liebherr - to 475 trucks from earlier 120.

Fortescue, the world's fourth-largest iron ore miner, expects to buy 360 autonomous battery-electric trucks, 55 electric excavators and 60 battery-powered dozers to replace about two-thirds of its current mining fleet.

The company's mining fleet consumed about 450 million litres of diesel in FY24 and accounted for 51% of its scope 1 carbon emissions.

The iron ore miner has been exploring various strategies to produce green iron - the iron produced with a lower carbon footprint, while also expanding into production of hydrogen from renewable resources.

"This is an important next step in our 2030 Real Zero target – to eliminate emissions from our Australian terrestrial iron ore operations by the end of the decade. The world needs Real Zero now – it simply cannot afford to wait," Fortescue Executive Chairman Andrew Forrest said in a statement.