Asked whether she would refer the deal to the Independent Commission Against Corruption,Ms Berejiklian said"that could very well already have occurred",adding she believed the matter needed to be investigated in the"fullest way".
"At face value,there are sufficient questions there that needed to be answered,"she said on Monday.
"I am extremely concerned by what I've read. I have seen what's on the public record and I'm extremely concerned by it and I think it warrants appropriate investigation."
Asked again whether it should go to ICAC,Ms Berejiklian responded:"Potentially – absolutely."
Transport Minster Andrew Constance has asked the NSW Auditor-General to review the matter,saying he expected"full openness,transparency and accountability from Transport for NSW".
But former auditor-general Tony Harris and former counsel assisting the ICAC,Geoffrey Watson,have called for the deal to be investigated by the anti-corruption watchdog.