Key Points:

A revamped Carlaw Park would have too little space for people spilling out of the stadium after a match, Rugby World Cup Minister Trevor Mallard says.

Mr Mallard and a former spokesman of a Carlaw Park supporters group yesterday dismissed a bid by a rebel faction of Auckland City Council to push the case for the park to host the 2011 Rugby World Cup.

The Government announced on Friday it favoured a $500 million waterfront stadium over plans for a $320-$385 million upgrade of Eden Park.

Rugby World Cup Minister Trevor Mallard has given Auckland City Council (ACC) and Auckland Regional Council (ARC) two weeks to reach agreement on which site they favour.

Auckland Mayor Dick Hubbard has publicly stated ACC's support for the waterfront stadium, but a group of nine of the 20 councillors last week launched an 11th-hour bid to persuade the Government to upgrade the disused Carlaw Park.

Yesterday some of the councillors and ACT leader Rodney Hide -- calling themselves the Domain Stadium Promotion Group -- said the waterfront option was "weak", "a pipedream" and its location "vandalism".

Prime Minister Helen Clark today said she did not agree with those who believed a stadium would wreck the waterfront.

"I personally don't believe that. I believe it would be an asset and I think that over time Auckland is going to look at how it regenerates that whole waterfront downtown area and having it as a major entertainment, recreational precinct, with the ability to host large events I don't think is a bad thing at all," she said on NewstalkZB today.

Helen Clark today said it was up to Auckland to make a decision.

"I think the waterfront has a lot that is compelling about it -- particularly the multiple use that it could have -- but at the end of the day we have to have a decision, Auckland has to be happy with it and we have to get on with it."

She said both sites had difficulties that needed to be worked through.

"But the issue really is what kind of legacy Auckland really wants from the Rugby World Cup," she said.

"I think Auckland's got the ability to have a major legacy of infrastructure from the World Cup and a national stadium would certainly be that."

Helen Clark said she was confident Aucklanders could decide on an option that allowed the city to host the Cup.

The Government has said if Aucklanders cannot agree than Christchurch will host the Rugby World Cup final.

"From my point of view as a passionate Aucklander and a passionate New Zealander I want to see our international city of scale, which is Auckland, host this cup and I think most Aucklanders do."

She said the fact Carlaw Park was private land was a major hurdle to surmount.

Auckland Councillor Richard Simpson said Carlaw would be cheaper and would not blight the waterfront's landscape.

But Mr Mallard yesterday dismissed their proposition on the basis a private developer already had a contract for the area, three hectares of the domain would need to be used and several hundred trees felled.

Today he said roading also ran too close to the proposed area for the park leaving inadequate space for people filling a 60,000 seat stadium to spill out on to afterwards.

"Probably the biggest problem is location relative to roads," he said on National Radio.

"People coming out of it would have to spill over, whereas on the waterfront for example there's going to be a boulevard which is going to be closed off.

"So there are a lot of reasons for it not being a runner, but it has been looked at very clearly."

Mr Mallard said he did not believe the rejection of the waterfront option by members of Auckland City Council's urban design panel reflected the opinion of all architects and designers.

"People involved in urban design within the planning part of the council have been really excited by it. I think design is very much in the eye of the beholder."

He said councillors needed to focus on a choice between the waterfront and Eden Park.

Former Coalition for Carlaw spokesman Cameron Brewer also yesterday called on the councillors to stop flogging a dead horse and focus on the two remaining options.

Mr Mallard said on Friday if Aucklanders preferred Eden Park, the Government would accept that, but if the region could not agree on a venue then Christchurch's Jade Stadium would host the Cup.

The waterfront proposal has the backing of the New Zealand Rugby Union.

The ARC is yet to take a position.

The waterfront option, including the building of the required platform across Captain Cook and Marsden Wharves, is estimated to cost $497 million.

The cost of an Eden Park upgrade varies between $320m and $385m, depending on final choices.