London, England - A group of Christian academics promoting the Biblical story of creation in school science lessons have been told to end their campaign.
In a letter, officials at the Department for Education and Skills told the group that creationism and its more recent off-shoot, intelligent design, have no place in the national curriculum and schools should refuse to use their teaching materials.
The move comes amid growing debate over the use of religion to debate Darwin's theory of evolution in GCSE and A-level science.
Truth in Science, which is funded and supported by prominent academics, teachers and clergymen, sent lesson plans to 5,700 state and private schools in September as part of a £20,000 campaign to promote alternative interpretations of the origins of life.
The teaching packs - a booklet and two DVDs - ask schools to consider that certain features of the universe cannot be explained by natural selection, but are best explained as the work of an "intelligent designer".
Backers deny that they actively promote the strict Biblical theory that God created the world in six days.
But this week Jim Knight, the schools minister, issued its strongest statement yet that creationism or intelligent design have no place in science lessons.
Answering a Parliamentary Question on Monday, Mr Knight said that the DfES had written to Truth in Science outlining its position.
"Officials have responded that schools are under a duty to follow the science programme of study which sets out the legal requirements of the national curriculum," he said.
The letter also states that neither intelligent design nor creationism is a recognised scientific theory and they are not included in the science curriculum.
"The Truth in Science information pack is therefore not an appropriate resource to support the science curriculum. The letter also mentioned that the department is working with the Qualifications and Curriculum Authority to ensure that schools are completely clear as to the reasons for this position."
However, he said that such material would be appropriate in religious education lessons.
"Creationism can be explored in RE as part of developing an understanding of different beliefs," he said, adding that it was up to schools and local authorities to "set the syllabus for how this should be done".
But, in another twist to the row, Truth in Science issued its own statement denouncing the Government advice.
In a message on its website, it said: "The national curriculum is a minimum standard. It exists to guarantee that every young person receives a basic education.
"Teachers are free to teach more than the minimum requirements of the national curriculum. Even if intelligent design is 'not included in the science curriculum', this simply means that it is not compulsory in all schools. It does not constitute a ban."
The DfES said it did not know how many schools were employing the teaching packs, which were drawn up with the assistance of four academics from the universities of Leeds, Bristol, Sheffield and Cardiff.
Truth in Science boast that at least 59 schools may be employing them.
An early day motion, signed by more than 40 MPs, has called for the Government to properly investigate the claims.