The Acting Chief Medical Officer says social distancing guidelines for schools could be further relaxed over time.
Government guidance published this week shows children up to third class won't have to social distance.
Those from 3rd to 6th class will be asked to keep one metre apart - and it'll be 2 metres for secondary school students where possible.
Dr Ronan Glynn says the rules could be relaxed, but only if the situation with Covid-19 continues to improve.
He says practical realities were taken into consideration when coming up with the guidelines.
Dr Glynn says: "I think there was a pragmatic acceptance that young children in national school are unlikely to socially distance at all times.
"The guidance, however, is clear that where possible that one metre should be kept and that children should be encouraged to socially distance,
"And to take on all the other measures that we are recommending."
Dr Glynn assumed the role of Acting Chief Medical Officer after Dr Tony Holohan announced his decision to step down yesterday evening.
Dr Holohan stepped down from his role to be with family, as his wife enters palliative care for cancer.
Dr Holohan requested privacy for him and his family.