BHP will spend £45 million ($82.9 million) increasing its stake in copper explorer SolGold, under a private placement that increases the chances of a bidding war with rival miner Newcrest Mining.

BHP will own 11.2 per cent of SolGold after completion of the private placement with the junior explorer this week, in a move that highlight's the mining sector's growing enthusiasm toward Ecuadorian copper acreage.