Describing the proposed rebuilding of the school, community centre and synagogue as "a model of how a shrinking community should recognise reality and use its limited but valuable resources to best effect", the report was concerned as to how long the schools could remain Jewish.

It said: "While the percentage of Jewish children in the secondary school is currently around 23 per cent, those in the entry Year 7 constitute only 17 per cent.

"There will come a time when the number of new Jewish children each year will be less than 10 per cent. Without any change this will eventually feed through to the total pupil number.

"The question that the community and the local authority will need to ask eventually is:

"At what point, if any, will the percentage of Jewish children become so small that it is no longer sensible to run the school as a Jewish school?"

Despite the school's "limited timetable" for Jewish studies, the report acknowledged: "The Jewish knowledge, commitment and identity and the positive approach to Israel that is developed by both Jewish studies and the wider ethos of the school are likely to be greater than if the pupils were attending supplementary religion classes on a voluntary basis."

It added: "Finally, there is a positive impact on interfaith and inter-community relations of a large number of non-Jewish pupils learning about Judaism, Jews and Israel in a sympathetic environment." The report concludes that Liverpool's example could prove useful to other mainstream schools outside London forced to take in non-Jewish pupils.

But the report, compiled by Prof Leslie Wagner, also acknowledged that a small number of Liverpool pupils "whose parents are unhappy with the large non-Jewish majority at King David High School" attend Manchester's King David High School.

However, in view of Liverpool's KD, the Manchester school had "not actively marketed itself" in Merseyside.

No-one from Liverpool KD High was available for comment, but Rachel Rick, head of KD Primary School - the feeder for the High School - said: "We are really pleased with the number of Jewish children applying for the school in September.

"Nearly as many are coming in as are leaving Year 6. In September 25 per cent of the roll will be Jewish."

She added that the proposed new school campus should "strengthen the Jewish ethos of the school". She added: "We are very excited."

Manchester KDH chair of governors Joshua Rowe said: "We are happy for our school to serve the whole of the north. We have not marketed in Liverpool, from where we have eight pupils."