Finance Minister Steven Joyce has accused Auckland Council of not paying its share of the cost of fixing the city's transport network.
Auckland needs to spend $24 billion in the next 10 years on infrastructure under the Auckland Transport Alignment Project (ATAP), but is $4 billion short, according to Mayor Phil Goff.
"Auckland Council would need to come up with at least $200 million a year to meet the shortfall," he told business representatives in early March.
"I'm not going to ask ratepayers to shoulder that burden - it's not viable nor is it equitable."
But nor should taxpayers, says Mr Joyce. He told The Nation on Saturday while it's up to the council how much it wants to spend on transport, few issues are as important to Aucklanders.
"As an Aucklander, I think both the Government and Auckland Council should prioritise transport investment," said Mr Joyce.
"We're certainly doing it… unfortunately at the moment, the way the budget is set up for Auckland Council, they're looking at reducing their expenditure on transport over the next few years."
The Government has declined Mr Goff's request to introduce a regional fuel tax to bridge the funding gap. Failing that, he's also proposed a tourism levy, which has also been shot down by Wellington.
Mr Goff has claimed rates would have to rise 16 percent to cover transport spending if no alternative funding could be found.
"What I think is if I were them and sitting in their seats, and knowing how Aucklanders feel about transport… they can certainly afford that, and the question is are they going to make that step? We're putting a huge amount in," Mr Joyce says.
The total cost of the City Rail Link is yet to be finalised, but the likely price range will be included in next month's Budget.
"They haven't even got the tenders in for the actual construction yet," said Mr Joyce.
According to its website, Auckland Council currently spends $38 out of every $100 it gets from rates on transport.