In a report by Dow Jones Newswires, JPMorgan said if the miner’s cutbacks in production and capital expenditure – in particular its coking coal operations – were to lead to a 10% drop in contract mining revenues for fiscal 2010, it could lead to a 5.4% downgrade to Leighton’s net profit forecast for 2010.

JPMorgan said Leighton currently earned approximately $300 million from BHP, making it Leighton’s biggest customer.

Risks to Leighton’s near-term outlook have been identified by JPMorgan, which have resulted from the “emerging weakness in Australian resources and the Australian non-residential and Dubai construction markets”

“Importantly, we don’t believe these risks are properly factored into consensus estimates or management’s guidance so we can expect the stock to remain under downward pressure,” JPMorgan reportedly said in a client note.