BHP Group flagged delays and cost overruns of about 30% for its key Jansen Stage 1 potash project on Friday, even as the miner reported record annual copper production above 2 million metric tons and warned of a decline next year.

The world’s biggest miner by market value flagged rising costs and delays at a giant potash project in Canada and said it may sell its Australian nickel operations.

BHP Group Ltd. says the cost of the first phase of its Jansen potash project in Saskatchewan is going to be more expensive than earlier expectations. The miner now estimates the project cost will be in a range of US$7 billion to US$7.4 billion, up from an earlier estimate of US$5.7 billion.