British scientists are seeking permission to press ahead with controversial plans to create hybrid human and rabbit embryos.

Three teams in London, Newcastle and Edinburgh are due to make applications this month for permission to carry out the work as part of their stem cell research programmes.They are seeking licences from the Human Fertilisation and Embryology Authority allowing them to create embryos that are 99.9 per cent human and 0.1 per cent rabbit.

The scientists are also looking at the possibility of creating similar "chimera" embryos by mixing human and cow genes.

The aim is to find a ready source of "human" embryonic stem cells without the ethical problems of tampering with human life.

Making the chimeras would involve removing the nuclei from animal eggs and replacing them with genetic material taken from human cells.

The resulting embryos would be mostly human, but would also contain small numbers of animal genes.