The Irish Passport Service has temporarily paused processing routine applications while the Republic of Ireland remains in Level 5 restrictions.
However, personnel have continued to offer a same-day service for emergencies including bereavement, illness or medical treatment overseas.
A weekly urgent service is still also being provided for Irish citizens resident overseas who require a passport for local immigration purposes.
In such cases, applicants should contact their local Irish Embassy or Consulate General.
To assist with the wider response to Covid-19, passport staff have been redeployed into other, essential public service roles.
These have included contact tracing for the Irish health service and helping to facilitate the processing of Covid-19 related benefits.
The Department of Foreign Affairs has said passport staff "do not have access to private, personal data when working outside of our secure offices and so cannot process passport applications remotely.''
Normal processing of passports will resume under Level 4 restrictions or lower.
''We have significant experience in addressing high volumes of applications," a departmental spokesperson said.
The spokesperson added that they would "expect to clear any backlog in six to eight weeks and return to normal turnaround times as quickly as possible."
The number of Irish passports issued in 2020 dropped by 60% compared to the previous year.
Around 400,000 Irish passports were issued over the last 12 months - around 40% of the number issued in 2019.
Last year, more than 45,000 first-time applications were received from Northern Ireland and Great Britain.
The oldest online applicant was 100 and the youngest was two weeks old.