Uncertainty over Brexit is driving demand for Irish passports in Northern Ireland, with some post offices running out of forms, officials say.
Post Offices across Northern Ireland were called by the Irish Passport Service on Tuesday to be told more forms would be delivered.
One Post Office manager described the current demand as "crazy", adding that it was driven by fears over Brexit.
Belfast's central Post Office ran out of the forms on Friday.
Branch manager Irene Edgar said the demand was huge.
"High demand, especially in the last few weeks, means there is a stock and delivery issue," she said.
The Post Office in the border town of Strabane in County Tyrone has no forms, despite ordering them three weeks ago.
Branch manager Christine McNulty said the demand was "completely crazy".
"People are afraid, that's why they want their Irish passports, fear around Brexit," she said, when asked why the demand was so high.
Each application for a standard 10-year passport costs €80 (£71).
The branch manager of Bangor Post Office in north County Down, said whilst they still have forms they are running low, describing the demand in recent weeks as "absolutely massive".
"It is Brexit, people don't know what is happening and they want to be prepared," she said.
When will new forms arrive?
The Irish Department of Foreign Affairs says application forms have been dispatched to Post Offices in Northern Ireland that operate the Passport Express Service.
"All Post Offices should be re-stocked by tomorrow or Thursday at the latest," said a spokesperson.
"There has been a general increase in passport applications in recent years which is due to a number of factors, including a growing population and an increase in travel abroad."
The number of applications from Northern Ireland increased last year by 2%, from 82,274 to 84,855 - and is up from 53,715 in 2015.
Amanda Lamberton said her Rossdowney Park Post Office in Londonderry's Waterside had a lot of forms at the moment although they did run out last year.
"We are at the border as well so we would always have had a lot coming because of the Irish passport," she said.
"But there has been an increase in British passports as well, oddly enough."
The government warned that Britons travelling to the EU after Brexit may need to make sure their passports have six months left to run.
In Newtownards, County Down, the Post Office said it still had forms, although demand had increased - especially from entire families applying for Irish passports.
Post Office branches in Crossmaglen in south Armagh, Armagh City and Ballycastle in north Antrim still had forms but said that there had been a high demand in recent weeks.
Can I get an Irish passport?
You can claim an Irish passport (or Irish citizenship) if:
- You were born in the Republic of Ireland or Northern Ireland before 1 January 2005
- You were born in Ireland after that date but your parents were British or Irish citizens
- Your parents or grandparents were Irish citizens born in Ireland, even though you were born elsewhere
Several other exemptions apply for those resident in Ireland for extended periods, adoptions, children of refugees, and other special circumstances.