BANNING regular unleaded petrol and replacing it with ethanol fuel is a bipartisan policy made four years ago, NSW Premier Barry O'Farrell says.
Mr O'Farrell yesterday said reports the move was a change of policy were a case of "political amnesia".
From July, the Biofuels Act will see all regular unleaded petrol in NSW replaced with E10 - an ethanol-blended unleaded fuel.
However, 746,000 cars and 92,000 motorbikes won't be able to run on E10, and so there owners will be forced to use the more expensive premium unleaded fuel.
There are also concerns about a shortage of ethanol supplies locking drivers and riders into an ever-increasing cycle of rising fuel prices.
"The important thing to remember is this is bipartisan policy that was introduced following the 2007 election campaign, when both sides of politics supported ethanol-blended fuel," Mr O'Farrell said.
"To suggest, as some have today, that there's been a change of policy, that this has come out of the blue, is some kind of political amnesia for those who write politics."
Confidential cabinet minutes showed the government agreed to ban regular unleaded petrol and replace it with ethanol fuel despite being told it would push up petrol prices.
The government also decided the public should not be informed of the impending price increases at the bowser, it added.
Mr O'Farrell said it was a "shame" the public had not been better informed and a public campaign would be run before the change comes into effect.