Waikato-Tainui, which also had interests in Auckland land, had initially backed Ngati Whatua's plan to challenge Government in the High Court.
Mr Blair said he welcomed Tainui's moral support, but Ngati Whatua had decided to proceed independently to achieve clarity for the current and future generations.
Government ministers have argued that the right of refusal was not activated by its plan to sell off up to 500 hectares of Auckland land, which is currently owned by Government agencies.
They said surplus land could be sold for development if it was designated for "state housing purposes", and they believed that this definition was broad enough to allow selling it for housing developments.
Ngati Whatua wanted clarification on this issue, saying it appeared to be a breach of its Treaty rights.
The judicial review would focus on the process behind the sale of a plot of land in Massey, which is the first section earmarked for housing under National's new policy.
Labour's housing spokesman Phil Twyford said Government's "ham-fisted" handling of its housing initiative had made it inevitable that it would end up in court.
"The Minister's incompetent management of his portfolio has put in jeopardy thousands of homes that Aucklanders desperately need.
"If Nick Smith had done his homework and consulted iwi first, instead of insulting them by trying to circumvent their legal rights, he could have avoided this fiasco."