Global dairy prices have risen 1.1% at Fonterra's fortnightly auction, the first rise since mid-April.
The average winning price was $US4598 per metric tonne, with whole milk powder prices rising 2.2% and butter up 4.7%.
Cheddar and butter milk powder both declined.
Volumes also fell slightly for the first time since April, falling 2% to 23,700 metric tonnes.
BNZ economist Doug Steel said that while the jump in prices was not much, it was against expectations that they might continue to fall.