AUSTRALIA'S most influential businessman, Jac Nasser, has slammed the Gillard government's record on tax and industrial relations, saying that unpredictability is undermining investment and could push BHP Billiton offshore.

Addressing the Australian Institute of Company Directors yesterday, the chairman of BHP Billiton demanded the government deregulate the industrial relations system and stop targeting the minerals sector with taxes. ''I cannot overstate how the level of uncertainty about Australia's tax system is generating negative investor reaction. People don't know where it's going,'' he said.

"I cannot overstate how the level of uncertainty about Australia's tax system is generating negative investor reaction. People don't know where it's going" ... Jac Nasser. Credit:Josh Robenstone

Mr Nasser also had a shot at the Treasurer, Wayne Swan, who has declared war on mining magnates Gina Rinehart, Clive Palmer and Andrew Forrest, claiming they are using their wealth to shape public policy for their own betterment.

''Attacking individuals and specific industries doesn't build confidence in our country, nothing good comes of this,'' he said.