The Office for Standards in Education is being accused of disregarding Government promises by omitting any mention of sex education from the proposed new framework for school inspection.

When sex education became a compulsory subject, education ministers promised that the new system would be monitored by inspectors. However, not a word about it appears in the draft version of the slimmed-down inspection framework, on which consultation closed last Friday.

Protesters include Lord Kilmarnock, chairman of the parliamentary all-party group on Aids, and the Sex Education Forum, an umbrella group of around 30 diverse organisations. Lord Kilmarnock wrote to OFSTED: “It would appear that this omission, of what is now a compulsory secondary level subject, is in clear breach of the Government’s, and indeed your own organisation’s, stated commitment.”

The absence of any explicit reference to the subject - which became compulsory last September, with the proviso that parents could withdraw children from lessons without explanation - has alarmed campaigners who fear that it could become impossible to monitor the workings of the new system or the numbers of pupils removed from classes.

Work on the new document is proceeding swiftly, with the possibility that a revised version could be published by OFSTED as early as the end of next month. Sex education appeared in the previous version in the section relating to pupil welfare and guidance.

Lord Kilmarnock received assurances at the time when the sex education law went through Parliament from the then education minister, Lady Blatch, that inspectors would be obliged to comment on school policy and effectiveness.

She added: “It may well be that if a significant number of children are withdrawn in a school, a comment would be included in the report. Every single report will be made public.”

Professor Stewart Sutherland, the former chief inspector, also wrote to Lord Kilmarnock to explain what evidence of policy and teaching inspection teams would expect to find in schools.

The Sex Education Forum has also protested to OFSTED about its “disregard for statutory obligations and the express promises of Government”. Chair Anne Weyman wrote: “We are most concerned by the removal of the whole area of Personal and Social Education, including sex, relationships and health education, from the framework.”

Mrs Weyman said the previous framework had proved useful in encouraging schools to fulfil their statutory obligations on sex education, adding that the development of good practice in the pastoral curriculum was receiving renewed Government commitment in areas such as sex and relationships, drugs, anti-bullying strategies, careers and parenting. However, there were fears that such programmes were being increasingly marginalised under the pressure of the national curriculum. “The wholesale removal of personal and social, health, parenting, relationships and sex education from the framework can only reinforce this marginalisation and is out of step with the concerted efforts of health and education professionals to work in alliance to promote better practice and to meet the Government’s sexual and mental health targets ,” she wrote.

A spokesman for OFSTED said that the omission of sex education from the draft did not mean it would not appear in the final version. However, as a statutory subject, inspection teams were required to report upon it, even if this was not explicitly stated in the framework.