The Government says the almost $30 million it has paid out to consultants doing initial work on the IRD's massive IT upgrade or "business transformation" is money well spent.
In response to questions from Labour's revenue spokesman, David Cunliffe, Revenue Minister Todd McClay yesterday confirmed more than $29 million had been spent on the project's consultants since 2009.
According to information supplied to Mr Cunliffe by Mr McClay's office, that included $23 million paid to French IT consultant Capgemini.
Ex-Revenue Minister Peter Dunne two months ago confirmed the Government was proceeding with the project, which was expected to cost as much as $1.5 billion over 10 years.
Mr McClay yesterday said he was not aware whether Capgemini had provided an estimate of the total cost.
Mr Cunliffe believed the Government was likely to have been given advice on the cost of the project but was unwilling to disclose that information because it would then have to disclose it in the Crown accounts, undermining its chances of reaching its 2014-15 surplus target.
But Mr McClay said Cabinet had been presented with several options for the project and was to decide on which one later this year.
"When they do we'll have a clearer picture what the cost is."
He defended the $29 million spent so far on the grounds, "the more due diligence and advice we get in the early stages, the greater likelihood that Cabinet's in the best position to make decisions that New Zealand taxpayers will be happy with".