Education Secretary Gillian Shephard accepted in full the recommendations of a working party on school security, set up in the wake of the murder of London headteacher Philip Lawrence.
But even as she spoke, a row broke out about how improvements would be funded with John Major pledging that the Government would fund a programme "as speedily as possible" and headteachers warning that schools could not wait.
It was not clear whether the Government would come up with new money for security measures such as closed circuit TV cameras or whether the cash would have to be found from the existing Pounds 19 billion schools budget.
Mrs Shephard said funding had to be considered in the context of wider decisions on public expenditure and said she would be consulting shortly on next year's Grants for Education Support and Training programmes.
The working party recommended Government "take the earliest opportunity to make available . . . substantial new money specifically earmarked for the improvement of school security."
And it said the Home Office should give "every possible priority to soundly-based bids" from schools which have responsed to its Pounds 15 million CCTV Challenge scheme to set up neighbourhood closed-circuit television systems.
Headteachers attacked the Government for refusing to pledge immediate extra funding to make schools safe. David Hart, general secretary of the National Association of Head Teachers, accused Mrs Shephard of "hiding behind the Treasury" in her response to the working party's report.
He called for an immediate injection of at least Pounds 25 million from contingency reserves and said: "Schools cannot wait until next year . . . I am very disappointed that Gillian Shephard is playing down the funding priority. She is back-pedalling and hiding behind the Treasury and repeating the age-old rubric that money depends on competing priorities. This is a wholly inadequate response."
Doug McAvoy, general secretary of the National Union of Teachers, added: "I am very disappointed at the Education Secretary's refusal to commit new money to ensure the safety of children and staff. To leave this situation unaddressed is unacceptable. To throw school security into the melting pot of consultation on public expenditure generally is to let down all those who believed the Government would act."
The working group, whose 22 recommendations were toughened after the Dunblane massacre in which 16 children and their teacher were shot dead, has urged the Government to organise a national conference on school security.
Guidance is due to be issued by the Department for Education and Employment on security measures which have proved successful.
These are likely to include the importance of security fencing linking outlying school buildings, communication systems to link teachers, card entry schemes and limited points of access.
Labour pledged co-operation on any new legislation needed to improve school security.