Cardinal Sean Brady told Catholic school heads that no child should be “sacrificed on the altar of experiment”.

The education minister has said the transfer test will end this year with pupils deciding their next move at the age of 14.

School principals, governors and trustees say, however, that they are concerned by Ms Ruane’s so-far ineffectual efforts to detail exactly what system will be introduced by September 2010.

Addressing the Shaping the Future Together conference yesterday, Cardinal Brady said trustees – the owners of Catholic schools – were happy to engage with the Department of Education in managing a “plethora of change”.

“It is vital that the minister ensures that there is root-and-branch cohesion across all these initiatives. Thus, it is one thing to announce that the end of the 11-plus and a transfer at 11 based on parental election,” he said.

“But before that can have any meaning there need to be systems in place to promote an area planning process – and that will not be possible without a clear sustainable schools policy.

“Otherwise some schools face a very uncertain future and will continue to die a slow lingering death.”

A society was uncivilised if it left the educational welfare of its children, especially its weakest, to the vagaries of Darwinian economics, Cardinal Brady said.

Trustees, he said, were working on social justice, not just responding in a self-centred manner to demographic trends.

“However, this exemplary post primary review process will not be able to continue unless the department gives coherent policy coverage,” Cardinal Brady said.

“If we get clear directions and support from DE [Department of Education] and from the minister, we have the potential to develop a wonderful, robust system of sustainable schools into the future.

“Without that clear guidance and appropriate sequencing of initiatives we risk removing the old and replacing it with chaos.”

Responding last night, Ms Ruane said: “I welcome the conference by the Commission for Catholic Education.