Irish planning on traveling internationally for their summer vacation are being warned there is a large delay in processing Irish passport applications following Brexit.

People in Derry have been urged to leave plenty of time for their Irish passport applications, DerryNow.com reports.

Sinn Fein Derry City and Strabane District Councillor Colly Kelly said: "Over the last week, I have had a number of people contact me as they have not received their Passports in the time scheduled.

Hi @csryan30 unfortunately you didn't leave enough time for your application to be processed for your travel date

— Irish Passport (@PassportIRL) February 28, 2017

"We have been advised today that there are major delays with passport processing as there are over 60,000 passports currently in the system. Brexit is having a major impact as thousands of applications are coming in from The 6 counties!

Got my passport today, just in the nick of time! Thank you @PassportIRL for getting it to me so promptly despite current demand!

— Amy Ní Riain (@Amyniriain) February 28, 2017

"The standard '15 day Passport Express' is not returning Passports in this time frame.

If you need to travel urgently for business, please use our appointment service https://t.co/avhTVz0A8C #UseTheRightChannel

— Irish Passport (@PassportIRL) February 21, 2017

"Therefore, please make sure to give them at least 28-35 working days to return your Passport before you travel until further notice. Allow extra time for lost passports and new passports for under 18s.

Hi all, we are currently dealing with a large number of messages on Twitter today please bear with us we will get to you as soon as possible

— Irish Passport (@PassportIRL) February 8, 2017

"If your date of travel clashes with this 28 working days advice, then please log onto https://www.passportappointments.ie/ and book an appointment with the Passport Office Directly in Dublin. For now, this is the only way you can be guaranteed to receive a Passport before you fly."

Irish are being warned to leave plenty of time for passport application processing following Brexit.iStock/Getty Images