Hapu spokesman Buddy Mikaere told the Herald he wants them out in the open.
"Here's our Government, signing secret agreements with a foreign company over something that has happened in New Zealand," he said.
"The Government has an obligation to its own citizens in the first instance, in our view, and not to a foreign company."
A spokesman for the ship owners said the nature of the settlement had already been addressed at the time it was announced, but could not disclose the specific terms or comment on the tribunal case.
"The terms as standard in any commercial settlement between two parties are confidential."
A spokesman for Transport Minister Gerry Brownlee said the tribunal would recommend whether the deeds needed to remain confidential.
The Government was meanwhile yet to form a position on a decision made by the owners to seek resource consent to leave much of the wreck on the reef after the site had been secured.
Ngai Te Hapu - which has wanted the ship gone since it grounded on October 5, 2011, spilling oil and debris on to the island and mainland beaches - argued that leaving the wreck would pose unacceptable consequences for the reef's environment and mauri, or life force.
Given the hapu's size and funding challenges, Mr Mikaere said it would ideally like to challenge the company's consent application in a united front of Tauranga iwi.
"Otherwise, it's cake stalls and raffles."
Tauranga Moana Iwi Leaders Forum chairman Awanui Black believed iwi preferred the wreck gone, a stance he felt was also the nation's, but leaders had not yet met to discuss their response.
Tauranga mayor Stuart Crosby also wanted the wreck off the reef, with a "sufficient bond" and a decade-long environmental monitoring process.
Mr Crosby was aware of issues regarding the documents.
"On one hand, I can understand that they are confidential agreements, but on the other hand, as we move forward, it's probably best that both the owners and Crown disclose as much as possible."
Representatives of the ship's owners and insurers are meeting Mr Crosby today as part of consultation with Bay of Plenty leaders.
Owners expect battle over wreck to go straight to court
A looming battle over the wrecked container ship Rena will go straight to the Environment Court, its owners expect.
The owners last week confirmed they would apply for resource consent, likely between the end of next month and May, to leave much of the shipwreck on Astrolabe Reef.
The company expected the matter would be directly referred to the court, with the alternative involving a hearing before council-appointed commissioners.
"As part of the proceedings ahead, there will be further opportunity for mediation on matters of interest before the application gets to a hearing stage," a spokesman said.
It was expected the entire salvage operation, which began after the ship hit the reef in 2011 and is still going, would ultimately cost the owners more than $350 millon.
Getting the wreck to an environmentally benign state continued to be a challenging task, with two divers already sent to hospital during preparations for removal of the ship's accommodation block.
Between two to three days cutting and lifting were required on the house, and there had been more than 80 days' specialist salvage dive preparations at depths of about 46 metres.
The spokesman believed there were misconceptions about the wreck, among them that the reef had been destroyed and that the wreck would continue to cause harmful emissions over time.
