Trade unions representing staff at Belfast Metropolitan College (BMC) have said management has been "deceitful" about the number of planned job losses.
Last week, the college said it believed it would have have to make "over 100" people redundant.
However, unions have said they understand the figure will be "closer to 200 posts".
They described the previous estimate as "duplicitous, dishonest and deliberately misleading".
A joint statement by the Northern Ireland Public Service Alliance (Nipsa), the University and College Union (UCU) and the NASUWT said they had received new information from management.
The statement said it set out plans for reducing the college's workforce 1,000 strong workforce by 20%.
BMC has said the redundancies were necessary because it has been running a deficit for four years.
On Monday, it was unavailable for comment on the union's claims.
Monica Goligher from UCU said that "unions intend to resist these attempts to decimate jobs and educational provision within the Belfast Metropolitan College".
BMC currently has six campuses around the city.
Construction of a new campus in the Titanic Quarter is making significant progress and is due to open in September next year.
A new building is also due to be constructed in north-west Belfast. It is scheduled to open in spring 2012.
Finance has been secured for both projects.