The company resumed production at its Samarco plant with joint venture partner Vale SA in December, five years after a fatal dam disaster led to suspension of activities at the site and multiple legal cases.

BHP raised its full year expectations to 245 million tonnes to 255 million tonnes of iron ore in fiscal 2021, edging up from its previous forecast of 244 million tonnes to 253 million tonnes, pointing to a record year for output.

"It's not an awe-inspiring result, but what has really helped it, and Rio Tinto, is commodity prices," said David Lennox of Sydney-based Fat Prophets. "No doubt they will have a strong first half result."

Like its peers, BHP has gained from China's robust appetite for the steel-making commodity and said its Western Australia iron ore output rose 3.5% to 70.4 Mt for the quarter ended Dec. 31. UBS had estimated the output at 70.7 Mt.

Earlier this week, peer Rio Tinto logged a jump in iron ore shipments and said industrial activity in China had returned to pre-pandemic levels.

Iron ore last month breached the 1,000 yuan ($154.04) per tonne level for the first time on supply concerns and as commodity-intensive stimulus measures in China fuelled demand, sending BHP, Rio and Fortescue share prices to records.

However, BHP warned of an impairment charge of between $1.15 billion and $1.25 billion in its half-yearly results for fiscal 2021, related to its assets at New South Wales Energy Coal, which includes the Mt Arthur coal mine.

The charge suggests BHP has not been able to find a suitable buyer, as it looks to a demerger instead, said a banker who declined to be named because it was against company policy.

As well as facing growing reluctance by banks and funds to finance thermal coal given climate change concerns, Mt Arthur's lower quality product has been particularly hard hit by an unofficial ban on Australian coal imports into China.

(Reporting by Anushka Trivedi in Bengaluru and Melanie Burton in Melbourne; Editing by Vinay Dwivedi and Lincoln Feast.)