Legislation giving diesel users more than a month's notice before road user charges are increased, has been introduced to Parliament.
Last year, an overnight increase by then-Transport Minister, the Labour Party's Annette King, provoked outrage among truck drivers, who staged a nationwide protest.
Ms King said she gave no notice because when the charges were increased in 2007, there was a $17.5 million pre-purchase ahead of the deadline.
Now a bill has been introduced which gives 42 days notice before an increase.
However to avoid pre-purchasing, road user charges for heavy vehicles (more than 3.5 tonnes), paid before the prices go up, will be valid only for a month after the increase comes into effect.
The legislation exempts light, electric vehicles from road user charges, to encourage their uptake.