A deal between casino operator SkyCity and New Zealand prime minster John Key could soon be investigated by the Auditor General.
Green Party co-leader Metiria Turei has asked the Auditor General to look into the deal, which saw SkyCity emerge as the preferred bidder for the new Auckland conventional centre.
It is understood that in return for its investment, the casino operator would be allowed to significantly increase its poker machine holding, a move that Ms Turei claims "raises a host of very serious issues".
"We believe that several state sector guidelines and rules for the procurement of public services have potentially been breached. It is important that all the normal rules around government procurement have been followed," she said.
"If the rules have not been followed, and SkyCity has received an unfair advantage, then the process needs to start again."
The news comes after the Australian government decided to hold off on a national rollout of pre-commitment technology on its own pokies.