The multi-million-dollar Commercial Bay development in downtown Auckland, being built by Fletcher Building, has been delayed again.
The site was expected to open in March next year, and the new PwC Tower next to it to open the following month - a delay of up to a year on the initial timeframe.
That means the shops would not be open in time for the Christmas shopping season.
The latest construction delays have increased costs from $681 million to between $690m and $700m.
Project owner Precinct Properties warned costs could rise by another $10m and Fletcher could seek further extensions.
Precinct chief executive Scott Pritchard said he was disappointed but confident its contract with Fletcher would prevent it from having to cover the additional costs or claims by the embattled construction company.
Precinct has already withheld payments to Fletcher.
Fletcher Building confirmed the additional costs were within the construction provisions it announced in February last year.
It also confirmed it had brought a number of claims against Precinct and that further claims were anticipated.
However, it said it was bound by confidentiality clauses in the contract and would provide no further details.