Books that introduce homosexuality to children aged as young as four are to be launched in a selection of UK schools, under a pilot scheme that has sparked outrage from a number of religious groups.

The current controversy echoes the uproar in the Eighties when a similar scheme caught the imagination of the tabloid press.

"The most important thing these books do is reflect reality for young children," say Elizabeth Atkinson, director of the 'No Outsiders' project by Sunderland and Exeter universities and London's Institute of Education. "My background is in children's literature and I know how powerful it is in shaping social values and emotional development. What books do not say is as important as what they do."

Atkinson argued that the absence of gay relationships in children's books amounted to "silencing a social message", fueling playground ignorance which can lead to bullying and isolation for children who are gay or perceived to be.

The 'No Outsiders' project is being launched in 14 schools across the North East, South West, London and the Midlands. The scheme which is aimed at children aged from four to 11 it will be extended nationwide if it's deemed a success.

The project organisers have yet to reveal which schools are using the books, but faith group Christian Voice has vowed to investigate and create a protest to have the books banned.

Christian Voice director Stephen Green says, "The arrogance of people like Elizabeth Atkinson, using children as guinea pigs is outrageous and thoroughly wicked.

"The more you normalise homosexuality, and the more kids see images of homosexual relationships from schoolbooks and authority figures, the more kids think any crushes they have on children of the same sex - which is quite normal at 11-years-old - are valid."