Cardiff University has confirmed plans to cut 400 full-time jobs amid a funding shortfall.
The proposals to save money could also involve school and subject closures and school mergers, with nursing, music and modern languages among the subjects being cut.
The Cardiff University and College Union (UCU) called the cuts “cruel and unnecessary” and said it would fight plans for compulsory redundancies.
The university said it would only make compulsory redundancies “if absolutely necessary”.
Vice-Chancellor, Professor Wendy Larner said “it is no longer an option for us to continue as we are”.
She said the university needed to “take difficult decisions” due to “declining international student applications and increasing cost pressures, and the need to adapt to survive”.
“I know that these proposals impact some staff more than others and they will cause a great deal of uncertainly and anxiety for those potentially impacted,” she added.
Dr Joey Whitfield from Cardiff UCU said they were “absolutely shell shocked” by the “cruel and unnecessary” cuts.
“I’ve had colleagues in tears. They’ll damage our members, our students, the city, and Wales as a whole,” she added.
She said union members “are prepared fight any compulsory redundancies tooth and nail”.
Prof Larner said the proposals would result in a “a slightly smaller university”.
She said a formal consultation would take place, with the 400 job cuts equating to 7% of the workforce.
The subjects and programmes being cut also include ancient history and religion and theology.
Chair of the University and College Union (UCU) Cymru Estelle Hart said prior to the announcement that there had been a “lack of communication” by university bosses which was causing “anxiety” to staff.
The university had previously said it had to take action to address a £30m black hole in its budget with the pressure of increased costs and falling international student numbers affecting the whole higher education sector.
An offer of voluntary severance between June and September 2024 was taken up and approved for 155 staff and a second round closed earlier this month.