Since the introduction of Brexit in the UK, the transport of live animals between Ireland and the UK has changed significantly.
EU pet passports that have been issued before January 1st 2021 will be recognised for travel, any EU pet passports issued after this date cannot be used for transport when travelling to the UK. The UK has now introduced a new UK health certificate that needs to be used for transport if not using an EU pet passport. This health certificate will need to be completed by your local vet and endorsed by the Department of Agriculture before travel. A customs clearance agent in the UK is also required for all live animal transport.
The UK is now recognised as a third country to Europe.