The University of Sydney is under fire for its treatment of international students after suddenly changing the graduation date for one of its most prestigious business courses.

The move, announced last week, had threatened to put up to 80 per of the university's master of management students and their families thousands of dollars out of pocket for air fares, accommodation and visas they had already purchased.

Internal emails seen by Fairfax Media reveal that the decision to change the graduation date with only a few days' notice caused division between the university's faculties and its administration.

The manager of the university's business school program, Lance Graham, urged angry students to petition the university's administration, describing the decision to bring forward the graduation by up to three weeks with only a few days notice was "unacceptable to say the least".