Students at Trinity College Dublin have occupied the university's 18th century Dining Hall as part of a protest against a decision to introduce a €450 charge for students who fail exams and have to resit.

Today was the third day of unrest over the measure, which the college's Students' Union wants reversed.

Earlier, students also blocked access to the Book of Kells and blocaded several entrances to the university

However, the Vice Provost of the college told RTÉ News that the new €450 charge it introduced for some students is part of a package to make things fairer for students.

Chris Morash said that while 1,700 students who fail an exam will pay the new charge to resit, another 250 students will pay less for repeating a year.

He said that it was frustrating to see students at the college protesting against a measure that actually made things fairer for students.

Mr Morash said the college did not want to disadvantage students and that the net effect of the new measure was that students collectively would actually pay €200,000 less.

However, the college's students' union has rejected this.

The President of the College's Students' Union, Kevin Keane, told RTÉ News he could not believe the college could say that.

He said the charge was manifestly unjust on the students who were being asked to pay it.

A group of students began an occupation of the Dining Hall in the college, which is still ongoing.

A rally was held in Front Square, which was addressed by speakers including Senator David Norris and Solidarity/People Before Profit TD Richard Boyd Barrett.

Organisers say groups of protesters gathered in a number of locations, closing down the front gate and the Book of Kells.

Students involved in the campaign are also calling for affordable rental options for accommodation, and an end to increases in any student fees.

Additional reporting Sinead Morris