The pace of cuts to the college sector could create a "funding crisis" and staffing problems, MSPs have been warned.
Both Edinburgh College and the trade union Unison have voiced concerns about the impact reductions in funding could have. The National Union of Students said colleges face a £34.6 million reduction in support in the Scottish Government budget.
Unison has now warned MSPs on Holyrood's Education and Culture Committee: "The cuts in funding leave the sector facing enormous challenges." Edinburgh College warned: "The current pace of financial cuts runs the risk of creating a funding crisis and short term staffing and educational difficulties."
Both Mandy Exley, the principal of Edinburgh College, and Unison's Chris Greenshields are to give evidence the committee, which is considering legislation aimed at reforming post-16 education.
The Post-16 Education (Scotland) Bill includes provisions for college regionalisation, which could lead to colleges merging or working together more closely.
In a written submission to MSPs ahead of a meeting, Edinburgh College said the Bill could offer "a better future" for students, staff and others.
But the submission added: "We are very worried that this potential positive development will be undermined and damaged because of the pace of change relative to changes in funding and provision."
While it said college mergers had the potential to save "substantial sums of public money", it also warned: "Colleges will have to reduce costs rapidly to remain financially sustainable and there is a risk that opportunities for our students and our communities will be compromised."
In its submission, Unison said: "College regionalisation is about budget cuts, not improvement. Colleges have already cut over 1,300 jobs, courses including vocational courses like aeronautical and aircraft engineering, computer animation, digital gaming, green-keeping and horticulture have been cut. Thousands of people were unable to find a college place this year."
The union added: "Regionalisation could make a difficult situation worse. Instead of improving accountability and efficiency, the current proposals merely merge colleges."