DEFRA has recently published the following information:
As the Government’s Withdrawal Agreement Bill was agreed by Parliament and received Royal Assent, the UK left the European Union on 31st January 2020 and has now entered a transition period until 31st December 2020.
During the transition period, to travel with your pet to the EU until the end of December, you can continue to use your Pet Passport. If you don’t have a current UK–issued EU Pet Passport, you will need to speak to your vet. More information is available here.