Retiring BHP chief executive Andrew Mackenzie will exit the mining giant three months earlier than planned as his handover to Mike Henry progresses ahead of schedule.

Mr Mackenzie will now leave BHP on March 31 but will still hand the reins to Mr Henry on January 1, as previously announced.

The company had previously announced Mr Mackenzie would leave on June 30 to enable a smooth transition to 16-year BHP veteran Mr Henry.

Mr Mackenzie has been chief executive of the world’s biggest miner since 2013.