A petition seeking to reduce the secrecy surrounding the Trans-Pacific Partnership trade negotiations was presented at Parliament yesterday.

Welcomed by Labour and the Greens, it was signed on behalf of several unions and non-governmental organisations, the Society of Authors and IT industry group NZRise.

It seeks as a matter of urgency a select committee hearing on the TPP talks, even if it is constrained by a lack of hard information. It also asks Parliament to resolve that New Zealand should take the lead in seeking agreement from the other eight countries in the negotiations to the release of draft texts and other documents.

And it wants a parliamentary resolution requiring the Government to release unilaterally the documents it has tabled, including its offers on services trade, investment, government procurement and market access for goods.

Professor Jane Kelsey, of Auckland University law school, said there were precedents for doing that, including WTO negotiations on trade in services.

"Release of documents always generates debate and sometimes means that agreements are never concluded. That is not a reason for continued secrecy. It shows that people weren't convinced that the agreement was in the national interest," she said.

Labour's trade spokeswoman Maryan Street said she wanted as much transparency as possible without jeopardising New Zealand's interests. She said unless statements could be contested by stakeholders no one could be certain that what was being offered was in New Zealand's best interests.

Green MP Catherine Delahunty said the public had a right to know what was being negotiated and whose rights were being negotiated away.

Trade Minister Tim Groser said there was no way New Zealand would unilaterally release information without the agreement of the other negotiating countries, which he considered unlikely.

Groser said it was the height of naivety to think trade deals could be negotiated in the open.

"They are very difficult and require countries to shift from long-held positions. That's why they take so long and many of them fail."

The Government would continue to consult with legitimate stakeholders.

But he said many of those pressing most strongly for transparency had never seen a trade deal they liked.