Specialist adult education colleges are campaigning to stave off the worst of the proposed budget cuts as they fear the spending review could put their future in jeopardy.
Colleges such as London's City Lit and Morley College, along with the Workers' Educational Association, are mobilising students and staff in a letter-writing campaign to win MPs' support in fighting off Treasury pressure for cuts of up to 40 per cent in real terms over four years.
Peter Davies, the principal of City Lit, in central London, said there was an additional risk that the pound;210 million adult safeguarded learning budget might be slashed or removed altogether.
The safeguarded budget preserves some courses which do not contribute to Government skills targets and is relied upon heavily by the specialist adult education colleges.
"My worry is the extent to which the Treasury is looking at the adult safeguarded learning budget," Mr Davies said. "About pound;5 million of our pound;7.5 million budget comes from this - we could be left with just pound;2.5 million.
"If that were to happen, it would have massive implications for us - it could put our whole survival into question."
Adult education faced being increasingly restricted to middle-class fee- payers, he warned, as colleges' policy of subsidising work with the unemployed, homeless people and other disadvantaged groups would become unsustainable under substantial cuts.
Over the past three years, the college has seen the numbers of students on benefits, and who are not charged full fees, rise by a third, with the influx driven by the rise in the unemployment rate and a desire among those out of work to retain and learn new skills.
Mr Davies said: "If we have serious cuts then we will not be able to maintain this approach of protecting concessionary fees and, thus, we could end up reversing this positive trend and really disadvantaging the less well off - exactly the opposite of what the Government is probably hoping for."
Richard Bolsin, the general secretary of the Workers' Educational Association, said cuts to other departments could also affect the association's work with disadvantaged groups.
"Adult learning is much more than classes for basket-weaving," he said. "It has a massive effect on people's lives and their communities. Our concern is that the sort of networks which we work with and which are quite delicate could be lost."
Cuts to the Department of Communities and Local Government could threaten outreach work, he said - for example the mental health support groups in the community which help bring learning to individuals who are otherwise hard to reach.
Adult education colleges are particularly vulnerable to the proposed cuts in the Department for Business, Innovation and Skills because they have no 16-19 provision, where the cuts are likely to be milder, to offset the losses.
A petition started by Morley College calling for the spending review to recognise the importance of adult learning and to prevent serious damage to the specialist colleges has attracted more than 1,100 signatures in less than a week.
Fircroft College of Adult Education, in Selly Oak, Birmingham, Hillcroft College, in Surbiton, Surrey, Northern College in Barnsley, South Yorkshire, Ruskin College, Oxford, and London's Mary Ward Centre and The Working Men's College are all also at risk from severe cuts to the adult education budget.