Labour is the only one of the three main parties opposed to fees — something that could be an issue in any programme for government negotiations with Fine Gael.
But it refused to rule out some form of contribution from students, which could include a graduate tax or student loan scheme.
Education spokesman Ruairí Quinn said that while “access” to third level should be free, “this does not mean education is free.”
Asked if students could be sure that Labour in Government would not impose some form of fees, he said the party’s position remains “exactly the same” but “we are in a very difficult economic situation.”
He said: “As to what we can do next September, quite honestly we are going to have to look at that in the context of budgetary constraints and everything else and where it is.”
Mr Quinn was speaking at the launch of the Labour party’s policy on improving literacy among school children, particularly in disadvantaged schools.
The party believes teachers should spend at least 120 minutes a day on improving reading and writing skills among pupils through the teaching of the normal curriculum rather than adding it as a new subject.
Almost one-in-six 15-year olds — the figure is one-in-four for boys — do not have the literacy skills to cope with further education or the demands of today’s workplace, according to a 2009 OECD skills survey.
Mr Quinn said improving literacy does not need more resources, just more joint-up thinking in schools. And he believes reducing class sizes is not the answer.
“Overall child literacy rates in Ireland have not improved since 1980, despite more investment and smaller classes,” he said.
And he pointed out that the former governor of Mountjoy prison. John Lonergan, had repeatedly stated that the majority of inmates could not read or write.
“We are going to make literacy a national cause. Dublin is the city of writers — Unesco approved. And one third of working class kids are illiterate.
“We pride ourselves on our great literary tradition. But we have excluded 10% population from even understanding, let along comprehending, that tradition.”