Labour supported the Taxation (GST and Remedial Matters) Bill through its first and second reading but has now withdrawn its support, Nash said.

"The LAQC changes have been introduced through the 70-page Supplementary Order Paper (SOP) which was only tabled by Peter Dunne on Wednesday [December 8]. SOPs are normally used to make very minor amendments and improvements, not generally to introduce substantial new legislation like this one."

"It contains a number of changes to tax legislation that impact upon a lot of people and it is simply not right that Peter Dunne can arrogantly introduce it without any consultation. It is outrageous," Nash said.

He said the changes were of particular significance to those with rental properties.

"There are more than 130,000 LAQCs and at least half of all rental properties are held in an LAQC entity. All New Zealanders from tax experts through to rental property owners deserve the right to be heard on such important legislation, but Peter Dunne's unacceptable arrogance is denying them."

Nash said the changes apply to more than $2.25 billion per annum of tax losses through LAQCs and impact on major issues such as the fairness of tax treatment of different asset classes.

"National had the chance to pass this Bill by consensus - but they blew it. The substance is hugely significant and the process is appalling."