During the transition period your travel in, out and around Europe remains visa-free so you do not need any supporting travel documents. During the transition period you can continue to travel freely without the carte de séjour residency permit. During the transition period these will continue to function as normal, making travel with your furry friend a fairly frictionless experience. After the transition period ends things are less clear as, for some inexplicable reason, the Withdrawal Agreement focuses mostly on humans. What happens during the transition period is fairly clear, but after that is over there are still many uncertainties.

Source: The Local January 13, 2020 09:11 UTC