The Government is considering passing a law overriding Eden Park's consent process because of fears it will not be ready for the Rugby World Cup.
The stadium still needs consent for its final stages and the Eden Park Redevelopment Board is concerned this could get bogged down in delays and appeals.
The consent includes the 10,000 temporary seats needed to get the stadium to the 60,000 capacity - a requirement agreed to with the International Rugby Board when it gave New Zealand hosting rights for the 2011 tournament.
Rugby World Cup Minister Murray McCully said the usual consent process involving the council and subsequent court appeals "now looks like an impossibility in the available timescale".
"This is obviously the nastiest shock that an incoming Minister for the Rugby World Cup could expect to receive."
Mr McCully said he had briefed Prime Minister John Key, "and he is as underwhelmed as I am".
The option of a Government "call-in", where projects of national significance are fast-tracked to speed up the consent process, did not give certainty.
The Government would therefore give "serious consideration" to legislating "because that is the option that delivers absolute certainty, and certainty is what we need."
Mr McCully said there were questions to be answered: "I want to fix the problem first, then point the finger of blame later."
The stadium is on schedule, with construction of the south and west stands well underway. The outstanding consent application covers a range of issues including the temporary seating, pedestrian access, the transport hub and the loss of a promised public space on the number two ground.
It will go to the Auckland City Council early next year for a hearing, and be open to appeal at the Environment Court and possibly the High Court.
Even processed as quickly as possible, this may finish only in the later half of next year. Some of the initiatives needing consent are set to start in September if the redevelopment is to finish its permanent projects by its own deadline of 2010.
Eden Park Neighbours Association chairman Mark Donnelly said the consent contained several issues that were "minor points for the World Cup, but major ongoing issues for the community". The community was unlikely to stand in the way of the temporary seating, but was concerned at other issues that might be rammed through.
Mr Donnelly said if the Government legislated, it would essentially be making a law to remove open space and carparks. "It is deeply worrying the National Government would start its term with such a slap in the face to due process."
Eden Park Redevelopment Board chairman John Waller said the call-in or legislation might not be necessary, but considering them was "prudent".
"If we went through the process and there were appeals and all that kind of thing it would push the time out."
Mr Waller said some residents might be upset if it happened, but "in this job you can't please everybody".
Labour Rugby World Cup spokesman Trevor Mallard said Mr McCully was "overreacting" by considering a law change. The outstanding consent issues were all minor, and if action was required, it could be dealt with by the call-in process, which saw the Te Mihi geothermal plant approved within six months this year.
The call-in combines the council and possible appeal into one board of inquiry, and still allows input.
