The Government should release all information relating to their decision not to purchase an emergency response multi purpose vessel that could have removed oil from the Rena, says the Green Party.
The call comes in response to news the New Zealand Maritime Union advised the Government over a year ago to purchase such a vessel to assist in the event of an offshore oil spill.
"The Government was advised to purchase an emergency response vessel over a year ago and after considering it they chose not to," said Green Party oceans spokesperson Gareth Hughes
"The public needs to know who made the decision not to purchase an emergency response vessel and what were the reasons for the decision.
"Having an emergency response vessel on hand for the clean-up could have made all the difference in the five days of calm weather to get oil off the ship.
"It is becoming clear that Maritime New Zealand didn't have the resources to deal fast enough with a significant oil spill and that's something we need to look into.
"A specialised emergency response vessel that could have got oil of the Rena seems like a minimum piece of response equipment New Zealand needs."
The Government also advised the Maritime Union that the Ministry of Economic Development was reviewing New Zealand's offshore petroleum operations in light of the Gulf of Mexico oil leak.
"The public are demanding answers from the Government about their slow response. We need the immediate release of all information about their preparedness for an oil spill."
"We support the call of the Environmental Defence Society for Royal Commission into the Rena disaster. However that shouldn't stop the Government releasing information now that is critical to our understanding of why the immediate response was so slow."