BHP Billiton boss Andrew Mackenzie says West Australian Premier Colin Barnett is "completely wrong" to suggest the mining giant and Rio Tinto are flooding the iron ore market and placing downward pressure on prices, which could potentially squeeze out smaller players.

Mr Mackenzie, speaking to reporters after BHP’s London annual general meeting, said the last time the board sanctioned a major project on iron ore was in 2011. “What you are seeing now is the impact of those projects coming through,” the chief executive said on Thursday. “But much more fundamentally,…