Funding for English language classes is being cut by half and for literacy and numeracy by a third over two years, despite ministers' assurances that basic skills would be supported.
The skills investment strategy, unveiled last week, promised that "literacy and numeracy provision will continue to be fully subsidised for all adults", with business secretary Vince Cable outlining his concern that half of employers were worried about basic skills.
Mr Cable told the Association of Colleges conference: "The Government will ensure, therefore, that funding for skills training is re- focused on those who need it most. In particular, a basic entitlement for those basic skills of literacy and numeracy needed to access employment and participate in society.
"We will ensure those who have left school without basic literacy and numeracy skills have access to free training, and we will make that training more effective."
But removal of the "programme weighting" - extra money to reflect the difficulty of teaching some of the most needy students - along with the general 4.3 per cent cut to adult education will mean a pound;1,300 per student cut to English for speakers of other languages (Esol) and a pound;660 cut to literacy and numeracy courses.
Added to similar cuts from last year, funding has fallen by 50 per cent for Esol and a third for other basic skills.
Alan Tuckett, director of adult education body Niace, said: "This is hard to square with the assertion that literacy and numeracy provision will be fully subsidised for all adults who need it.
"I do think some things can be done to preserve quality on tight budgets but these levels of reduction will make it harder than it already is to meet the literacy needs of people with the lowest levels of skill."
Mr Tuckett said the cuts would put further pressure on colleges to focus on those with less severe need who could more easily be brought up to the qualification standard.
Successive governments' Esol policy had partly responded to advertisements in places like Poland urging people to come to Britain for free language training, Mr Tuckett said, but the problem was only likely to be resolved with a co-ordinated EU response.
Nick Linford, author of The Hands-on Guide to Post-16 Funding, said that, combined with abolishing Esol funding in the workplace, the changes would hit urban colleges hard.
He said that instead of making sweeping changes to provision for vulnerable adults, the Skills Funding Agency should have reviewed the weighting for all courses, to see if it was justified in the cost of provision.
He added: "Why not review whether equine studies needs a 72 per cent uplift? Unless they can show their evidence on what impact this will have on delivery, it seems lazy or unfair."
Editorial, page 6.