The Canadian Federation of Students is suing the student union at the University of Prince Edward Island for nearly $100,000 in unpaid dues.

Tim Cullen, the president of the student union in Charlottetown, said the group stopped paying dues to the federation in 2005 because it wasn't getting enough for its money.

"The relationship between the UPEI student union and the Canadian Federation of Students has been rocky at best," Cullen said.

"Around 2005, things really came to a head when the student union felt that [the federation] was not fulfilling all of its duties and was not providing the UPEI student union with all the benefits of membership in the organization."

The lawsuit has been filed in Charlottetown, and Cullen said the student union plans to defend it. No date has been set for a trial.