The Road Transport Forum wants the Government to end uncertainty about when a new road user charges regime will be introduced.
Passage of relevant legislation has been delayed partly because of Parliament's focus on bringing in special measures needed because of the Canterbury earthquakes.
The forum says the delays are creating a climate of investment uncertainty, which is having a significant impact on business confidence and productivity in the road transport industry.
However, Transport Minister Steven Joyce says it will be very challenging to get the legislation completed before the election in November.
