National ministers fear a $1 billion hole in the ACC budget could signal a much wider problem, putting huge pressure on accident compensation levies.
Prime Minister John Key said yesterday the corporation was seeking $297 million more for the current 2008/2009 year and similar figures for the next two years to fund the non-earners account.
The $1 billion account pays for the accident treatment of those not in the workforce and is paid from government coffers.
"We are facing major challenges across all the accounts," ACC Minister Nick Smith said.
The non-earners account was the only one that urgently needed cash and he was receiving advice on the state of the other accounts.
"The initial reports are very concerning."
Asked if suggestions of a 25 percent increase in medical costs were being faced by ACC, Dr Smith said he was getting advice from Labour on "substantial cost increases in other accounts".