(Updates with capital expenditure plan in paragraphs 2 and 6,...

(Updates with capital expenditure plan in paragraphs 2 and 6, company quote in paragraph 3, and details on net zero operational emissions in paragraphs 4 and 5)

June 21 (Reuters) - Australian mining giant BHP Group (BHP) said on Wednesday it was on track to reduce its operational emissions by at least 30% by 2030 from its 2020 levels, but that its path to achieving net-zero carbon emissions would be "uneven".

The world's largest listed miner said it expects to spend the majority of its capital expenditure budget of $4 billion only towards the end of the decade, as technology matures.

"Decarbonisation will be non-linear and will require significant effort to overcome emissions growth and technology challenges," the miner said in an investor presentation.

BHP also reiterated its goal of achieving net zero operational emissions by 2050.

Operational emissions do not include the carbon emitted by BHP's customers in steelmaking, one of the world's most heavily polluting industries.

BHP expects to spend 40% of its allocated capital on its Western Australia Iron Ore (WAIO) operations, its biggest asset in terms of revenue, between fiscal years 2024 and 2030, with Escondida copper project in Chile being allocated 31%.