MELBOURNE - The world's biggest listed miner BHP said on Thursday it was disbanding some global teams and transferring those roles covering functions including planning, environment and heritage protection to its mining asset-level management.

BHP employs more than 80 000 people in staff and contractors around the world and the announcement comes after CEO Mike Henry has flagged the lack of productivity improvement and high costs of its Australian workforce. The changes will take place at BHP's operational assets in Australia and the Americas.

BHP did not say how many jobs would be impacted if any, but the Australian Financial Review reported some roles related to a standalone planning and technical division and a unit for health safety and the environment have already been cut.

"As part of our continuous improvement in how we approach our work, we have made some changes to better align work activities within assets and support quicker decision making,” a BHP spokesperson told Reuters, after an email outlining the changes was sent internally.

The changes mean that responsibility for decisions around health, safety, environment, planning, heritage management, decarbonisation and rehabilitation will come under the heads of each operational asset, according to BHP.

In Australia, BHP's assets include Western Australian iron-ore, Nickel West, South Australian copper, Queensland metallurgical coal and New South Wales energy coal. In the Americas it includes its Chilean copper mines and Canadian potash.

Among other changes, warehousing and logistics roles will also become site specific rather than a global function, while operational decarbonisation will come under a national team supporting each country's assets, the company said.

BHP will keep group level teams in health, safety and security, sustainability and social value and its maintenance centre of excellence align standards, consistency, strategy and governance.

The restructure comes as BHP decides the fate of its loss-making Nickel West operations after a flood of Indonesian supply hammered prices in the past year.

Nickel West employs around 3000 staff and Henry said a decision was expected in the coming months when the miner announced a half-year underlying profit of $6.6-billion on February 20.