KiwiRail's Chief Executive has signed the CEO Climate Change Statement along with Fonterra and Z Energy bosses.
But the Rail and Maritime Transport Union is calling the move hypocritical green-washing.
Union General Secretary Wayne Butson says Labour and the Greens need to follow up on their pre-election promises.
He says they need to direct KiwiRail to stop its plans, continue the use of electric locomotives and do everything it possibly can to reduce its carbon footprint.
