Don Brash and Winston Peters formed an unlikely alliance today in protest against what they believe is "preferential treatment" for Maori in new planning laws.
The two men, once sworn enemies, united in criticism of proposals to change the way iwi are consulted in the resource consent process.
Dr Brash, the former National Party leader, was making a submission on Resource Management Act (RMA) reforms.
He said radical reforms of the RMA would do more than any other single measure to improve New Zealanders' standard of living.
However, the National-led Government's proposals were "pitifully limited" and "barely scratched the surface of what was needed".
The "cost" of progressing these "modest changes" was a significant expansion of iwi rights, he claimed.
The bill would "vastly extend" Maori involvement in the planning process by requiring councils to invite Maori to enter into what are known as "iwi participation agreements".
"This is surely a recipe for further delay, for corruption and for anger on the part of the rest of the community," Dr Brash said.
His old party had persisted with the changes despite being offered a "vastly better alternative" by Mr Peters.
The New Zealand First leader has offered to support broader RMA reforms in exchange for removing any iwi-specific provisions. It was "incomprehensible" that Mr Peters' offer was not taken up, Dr Brash said.
Maori Party co-leader Marama Fox was one of several committee members to challenge Dr Brash.
She asked what he thought of the Waitangi Tribunal's recent ruling that Maori did not cede sovereignty when they signed the Treaty of Waitangi in 1840.
"Very briefly, bollocks," Dr Brash said, prompting a chuckle from Mr Peters.
The New Zealand First leader then sought permission for Dr Brash to have his time limit extended, saying the iwi rights debate was "the biggest issue the Government will face this term".
The motion was denied, but the two men later continued their conversation in a pub on Lambton Quay.
In exchange for the Maori Party's support for the stalled RMA reforms, the Government last year agreed to require councils to set up plans to consult with iwi earlier in the planning process. Iwi were already consulted on planning decisions, but in an inconsistent fashion and often late in the process, which sometimes led to disagreement and litigation.
Environment Minister Nick Smith said that contrary to Dr Brash's claims, the changes in relation to iwi would streamline the consenting process.
"The real difficulty for councils where they are receiving thousands and thousands of consents is trying to differentiate where iwi have a proper interest.
Under the Iwi Participation Agreements, he said, "the council will know at the beginning that iwi have a particular concern about this water body and all those thousands of consents that are about building issues of which they have very little interest would not be involved."