Auckland Mayor Len Brown says the council faces tough choices as part of a new 10-year budget that kicks off today.
In a statement ahead of a budget committee meeting this afternoon, Mr Brown said the council would have to look at delaying "lower priority capital projects" for more significant projects.
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He did not mention the $2.86 billion city rail link, but Mr Brown is under pressure to come up with a funding package for the project, which he wants to start building in 2016.
"With Auckland continuing to experience strong growth, we will need to work hard to strike a balance between investing in vital infrastructure, and keeping our rates and debt low and sustainable," Mr Brown said.
The mayor said the council's AA credit rating was testament to careful and responsible financial management, but said there was no blank cheque to fund the city's growth.
"We need to be clear about the priorities in the Auckland Plan, and prepared to make tough choices in some cases," he said.
As well as delaying capital projects, Mr Brown said a full review of the council's budgets and work plan would investigate tolls and congestion charges for transport projects and efficiency.
The Government has ruled out tolls and a regional fuel tax to pay for transport projects.
National and Labour have both said they have no plans to change the way councils are funded after Mr Brown floated the idea of an income or GST tax to replace rates.