Cork Airport has published advice for passengers who could be affected in the event of a 'no-deal' Brexit in Britain.
The UK is set to leave the European Union on October 31st with a deal yet to be agreed between the two.
Some travel disruption at ports and airports is likely in any no-deal scenario.
If the UK leaves without a deal, the Garda National Immigration Bureau (GNIB), which operates immigration at Cork Airport, has confirmed that UK passport holders will continue to be processed through the EU channel.
However, this EU channel will be re-designated as an 'EU/UK' channel.
"This means there is no real change at Irish immigration for UK passport holders", the airport says.
In the event of no-deal, all passengers arriving from UK airports will have to use the Green or Red customs channel.
No passenger arriving from a UK airport is entitled to use the Blue channel - irrespective of their nationality.
Revenue Commissioners staff who manage Customs at Cork Airport will be on hand to help passengers and to deal with any queries that may arise.