Pro-life leaders have criticised senior judges in Britain for supporting assisted suicide in their judgment in the case of Ms Debbie Purdy.

Paul Tully, general secretary of Society for the Protection of Unborn Children said: "This judgment is plainly directed at getting the law changed, despite the insistence by several of the judges that that is not their purpose. None of the five judges suggests that it is wrong in general to help suicidal people with disabilities or degenerative conditions to kill themselves - and one suggests that bankruptcy or the grief of bereavement can be equally good reasons to commit suicide. Another of the Law Lords argues that some people assisting suicide should be commended for their criminal actions."

The judgment requires the Director of Public Prosecutions (DPP) to issue guidance on when he will or will not prosecute those who criminally assist suicide. The offence under the Suicide Act covers a person who "aids, abets, counsels or procures" the suicide of another. The judgment directs that the new policy should cover "a case such as that which Mrs Purdy's case exemplifies".

Paul Tully said: "The judgment reflects the context of a relative giving someone travel assistance to go to Switzerland or other place where assistance to commit suicide might be regarded as legal. However, the judges don't make clear, for example, whether they think those who encourage a suicide, rather than just assist the process, should be prosecuted. It is unclear what guidance is expected of the DPP on such points.

"Most people with long-term disabilities, degenerative diseases or terminal illness do not seek to commit suicide, yet their lives could be undermined by this judgment. They may feel under pressure to kill themselves because they think they are a burden on others.

All five law Lords agreed to Ms Purdy's demand that the DPP should publish a policy setting out the factors that will be taken into account when deciding whether to prosecute people for assisting suicide.

But pro-life commentators say that not only is the ruling dangerous but it is also unclear. The situation is being watched with concern by Irish groups such as the Life Institute who say that similar threats are imminent in Ireland. Niamh Uí Bhriain of the Institute said that the right to life of those with disabilities, the seriously ill and the elderly were under threat from such rulings.