Ministers are under pressure to overhaul a special educational needs system that MPs say is failing many pupils and is "not fit for purpose".
Members of the cross-party Commons education committee have accused the Government of "an abdication of responsibility" over the closure of special schools.
And their highly critical report, released yesterday, condemns existing arrangements as seriously flawed in terms of the consistency of provision, the process of awarding pupils statutory statements of special educational need and teacher training.
The MPs say the framework, introduced following the 1978 Warnock report, has "run its course" and are calling for national guidance on when SEN statements should be issued and minimum standards to end the current "postcode lottery". They also want councils to be legally required to provide a broad range of support for special needs pupils.
But Alan Johnson, the Education Secretary, said he does not believe it is the right time for a "completely fresh look".
The MPs said: "The evidence clearly demonstrates that SEN and the raising attainment agenda sit very uncomfortably together at present." Under a targets, testing and inspection regime, special needs pupils were inevitably less welcome because of concerns they might drag down a school's results, they said.
The report is the latest challenge to a system that has faced recent criticism from the Audit Commission, teaching unions, Ofsted and Baroness Warnock, its architect. Last year she backtracked on her original report, condemning statementing and the "blind faith" in educating special needs pupils in mainstream schools.
The report refers to guidance to local authorities, as part of the Government's 2004 strategy, which says that the proportion of pupils educated in special schools should "fall over time".
Yet Andrew Adonis, schools minister, told the MPs during their investigation that the Government had no policy of encouraging the closure of special schools. Now, the MPs want clarification: "The Government should be upfront about its change of direction on SEN policy and the inclusion agenda, if this is indeed the case."
The report also criticises the exclusion of special needs pupils and calls instead for extra resources and teacher training so that staff in mainstream schools are better equipped to cope. It recommends that funding agreements be changed to prevent academies from discriminating against special needs children.
The committee wants ministers to adopt a "pupil-centred" approach with no specific SEN category and all pupils considered individually with a sliding scale of resources to meet their needs.
Steve Sinnott, general secretary of the National Union of Teachers, backed the committee's findings and called for an independent review of government policy.
Mr Johnson denied it was policy to close special schools. But he said his department would look at the case for extra funds and consider whether further changes were needed to its strategy following an Ofsted evaluation.
David Siddall, whose daughter Bethany attends Mowbray special school in Bedale, North Yorkshire, welcomed the report. Bethany, 9, has a rare brain disorder and he said the extra attention she receives there allows her to flourish.
But proposals to merge Mowbray with another special school, leading to a net loss of 70 places, mean Mr Siddall is among a large group of parents who fear their children will end up struggling in mainstream settings.
North Yorkshire council is proposing a broad range of provision with more resources in mainstream schools and new special school buildings.
The shake-up will mean 158 fewer special school places but, as the authority points out, its plan is in line with the Government's 2004 strategy.