Ownership of many properties, including Auckland's largest inner-city mall, could change as plans for Auckland's underground rail loop edge closer.

The central city line could pass directly beneath the large multi-level Westfield Downtown on reclaimed land spanning Albert St, Customs St West and Queen Elizabeth II Square.

At the end of last year, Westfield valued the centre at $40.3 million and some property experts now believe negotiations between the council and Westfield could see ownership change.

The low-rise 13,964sq m mall in the waterfront block makes total annual sales of $68.1 million and Westfield has planned to redevelop the building, vastly undersized for the high-rise zoning and valuable location.


Linda Trainer, general manager of Westfield NZ's shopping centre management, would not say if the company had held discussions with the Auckland Council over selling the property so the rail project could go ahead.

But Westfield was well aware of the rail plans and it had permission to redevelop the site, she said.

In 2008, plans were floated for a 41-level tower with a new shopping centre on the lower levels and offices above, and the former Auckland City Council showed an interest in protecting the underground rail loop site then. Foundations for the new block would be so deep that no tunnel could be built.

But that was before the global financial crisis, which has caused many firms to retrench staff and rethink their property demands.

"Westfield NZ has a resource consent for an office tower [there] and is aware Auckland Council has plans for the city rail tunnel that would pass under the shopping site," Trainer said.

But nothing would happen until tunnel plans were advanced. "As neither the office tower nor the tunnel are committed, it's business as usual at Westfield Downtown," she said.

"Westfield NZ will continue to proactively review its assets to determine development potential as part of our normal business practice."

A city councillor said questions about buying the property should be directed to the council-controlled body Auckland Council Property.

Auckland Transport's proposed plan shows how the rail link would head north from Britomart then west.

The $2.86 billion link is a 3.5km double-track underground line running beneath the central business district from Britomart to the western line near the existing Mt Eden station, with up to three underground stations.

"Over the past decade, rail patronage has increased from 2.2 million trips a year to 9.5 million - a growth of 332 per cent," Auckland Transport said.

"The rail system is constrained by the limited capacity of the Britomart terminus. Changing Britomart to a through station will create a rapid transit system radiating from downtown Auckland that will boost central city life."

Clive Fuhr, acquisitions and disposals manager at Auckland Council Property, referred inquiries to Auckland Transport.

Negotiations are understood to be taking place to buy a number of properties and Auckland Transport says it is securing the line now.

"While discussions on funding and other essential steps [such as design and procurement method] are continuing, both central Government and Auckland Council have agreed it's sensible to protect a route now to enable future construction," Auckland Transport said.

"Auckland Transport is working towards confirming the route for planning protection."

An Auckland Transport spokesperson acknowledged images showed the line running from Britomart to Albert St but said there was no final footprint for the project yet.