The board of the National Archives say the service will be put under “untenable pressure” if Ireland follows the UK’s lead and changes the ’30 year rule’.

It has warned that the archives are severely short-staffed and could not cope with an increased workload.

Britain is changing the so-called ’30 year rule’ for state papers to a ’20 year rule’, with two batches of papers being released every year to catch up.

However, in its annual report the National Archives in Ireland says it would need extra space, staff and funding in order to keep up with the schedule followed by its British counterpart.