A lobby group opposed to genetic engineering is urging AgResearch to stop all of its work on animal cloning.
GE Free New Zealand says it's unacceptable that the Crown research institute is only changing the technology it is using for animal cloning trials instead of ending them altogether.
AgResearch has said that unacceptable death rates have persuaded it to change the way it is carrying out the trials, which are part of its transgenic animal research.
Applied biotechnologies manager Jimmy Suttie says only 10% of animals cloned by means of nuclear transfer technology survive.
Dr Suttie says all AgResearch cloning work is reviewed by an animal ethics committee.
But a GE Free spokesperson, Claire Bleakley, says the institute should be cancelling the work, not just switching to a different technology.
Ms Bleakley wants the Environment Risk Management Authority to re-evaluate what AgResearch is doing.