The Government is likely to back United Future's move to insert a reference to efficiency in the Land Transport Management Bill when Parliament next debates it on November 4.
The omission of economic efficiency as an objective of the bill was a major reason for criticism by transportand business lobby groups when it was reported back this month from the parliamentary transport and industrial relations committee.
The committee did insert a requirement that a road funder ensure any "activities" contribute "efficiently and effectively" to the relevant objective, which, however, might itself be counter to economic efficiency.
Larry Baldock, of United Future, wants to go much further.
He has proposed two sets of amendments. One substitutes the word "efficient" for "responsive" in the purpose of the bill, so that its purpose would be to achieve an "integrated, safe, efficient and sustainable land transport system".
There are consequential amendments to Transfund's and Transit's objectives.
The other proposed amendment changes one of the objects of the bill from ensuring land transport funding is "cost-effective" to "efficient and effective", which goes part-way towards reinserting economic efficiency.
According to Government sources, it is likely to support at least the second of these and may develop its own amendment to incorporate it.
But this still falls short of lobby groups' wishes for economic efficiency as an objective.