The University of Wolverhampton announced in May that it was halting student recruitment to 138 courses due to a £20 million deficit and a 10 per cent fall in UCAS applications.
The University and College Union (UCU) has now written to the Office for Students (OfS) urging it to investigate the plans, claiming they breach government regulations.
The union fears the move will see "significant" numbers of staff losing their jobs and will "have a devastating impact on current and future students as well as the local community".
Undergraduate and postgraduate courses from “across the university portfolio” are affected.
The OfS regulates universities and sets the requirements needed for an institution to be registered as a higher education provider.
In its letter, UCU claims the measures are so severe they put at risk the university’s registration status.
The letter claims by implementing course cuts on such a scale and in such a short timeframe the university is likely to be in breach of a number of OfS regulations.
The union claims these include "the regulatory objective to ‘ensure…students from all backgrounds…are supported to access…higher education’, as the closures mean local students will have much less choice in what they study and are therefore less likely to go to university".
And "the regulatory objective to ensure ‘all students receive a high quality academic experience’ as many students who have accepted offers from the university can no longer take up their places".
The letter draws particular attention to the situation of students studying performing arts.
The union claims all but seven teaching staff in the department are expected to lose their jobs before September.
UCU regional official Anne O’Sullivan said: ‘The OfS has a vital role in regulating higher education in England.
"It is abundantly clear that the cuts the University of Wolverhampton is forcing through will mean that future students in the local community will be denied opportunities to access higher education.
"Many prospective students who have accepted a place in September will no longer be able to attend Wolverhampton and current students will have their university experience damaged beyond recognition. These devastating cuts must be halted."
The university - which also has campuses in Walsall, Telford and Burton - has assured students on the 138 courses that they would be 'taught out' to the end of their degrees.
A spokesperson at the University of Wolverhampton said: “The University of Wolverhampton faces significant challenges, including the impact of the Covid-19 pandemic on the higher education sector and the effect on student recruitment to universities in our part of the sector. As such, we have recently taken a decision to suspend student recruitment for the forthcoming academic year to 138 of our courses across the university, giving clarity to prospective students as this critical moment in the admissions cycle, whilst allowing us to continue to review and reflect on our options.
“In making the decision to suspend recruitment we followed a rigorous review of our academic portfolio, with a focus on student outcomes, measured in line with the Office for Students’ metrics of continuation, completion and progression. We do not underestimate the importance of such a decision, to both our staff and students, nor do we fail to see the impact of the uncertainty caused by it – and we are doing our utmost to support them at this time.
"These are difficult decisions for the university to take at a highly challenging time in the sector for modern universities like ourselves however, these actions will allow us to further concentrate on those areas of strength for the university to grow and develop, ensuring we can deliver an excellent experience for our students, whilst ensuring the financial sustainability of their institution.”