KEY POINTS:
Politicians give their reactions to news that Don Brash has resigned as leader of the National Party.
National Party President Judy Kirk:
"In my dealings with Dr Brash, I have always found him to be a gentleman and it has been a privilege to work with someone of such high calibre."
[She described him as an outstanding New Zealander, who had made an extraordinary contribution to his country and party.]
Prime Minister Helen Clark:
"They're about to get their fifth leader of the National Party within nine years - there's tremendous instability in the party. They have an identity crisis.
"It would appear that probably the book is rather worse than they expected in exposing duplicitous tactics since the election campaign devised by Dr Brash and which of course Mr Key was a key partner. Until they sort out their identity crisis I think the future's a little bleak…
"I think the book has unquestionably been the catalyst for it, and the fact that it has basically been produced with the support of people who were loyal National Party supporters indicates how deep and troubling the turmoil within the National Party is…
"It comes as no surprise whatsoever. The only surprise would be that it hadn't happened earlier."
Deputy Prime Minister Michael Cullen:
"This continued instability in the National Party is a sign of a party still nowhere near ready to govern. Dr Brash's resignation was inevitable. But it solves little."
National frontbench MP Tony Ryall:
"I think credit will always be given to Dr Brash for rescuing the National Party from oblivion.
"We are all very disappointed for Dr Brash and for New Zealand that he is not going to have the opportunity to be prime minister."
National backbench MP Brian Connell:
"I feel very vindicated."
[The Rakaia MP was suspended from caucus after he questioned Dr Brash's fitness to be leader due to rumours about him having an affair.]
National MP Nick Smith:
"Don has been an outstanding leader who has made a huge contribution to the National Party, I think he has genuinely made the decision because he is a person of deep conviction…
"He believes that National will be better served with a new leader. I am not sure I agree with that."