A South Island iwi says it will withdraw its approval for the use of 1080 on the West Coast.

The Maori tribe says there is insufficient evidence that the poison is not harming untargeted wildlife.

The deputy chair of  the South Island Iwi, Terry Scott, says kiwi are not breeding in parts of the tribe's territory and they suspect 1080 is to blame.

But the TB Free West Coast Regional Council says a 1080 drop in the area has already been granted consent.

The Council says greater consultation, negotiation and compromise will now be needed between organisations wanting to use 1080 and iwi.