PET owners should speak with their vets now about travelling to the EU as animals could need blood tests and jabs after Brexit if pet passports are scrapped.
President of the British Veterinary Association Daniella Dos Santos warned it could take 3 months for pets to be ready to travel under new Brexit rules.
Ms Dos Santos told BBC Radio 4: "The Government have announced the three possible scenarios.
"One of them does need some planning in advance, which is why the Government is saying to contact your vet."
Michael Gove is set to lay out the Government's Brexit transition rules later today - as animal lovers wait to hear the rules their pooches will have to follow.
If the UK and the EU don't hash out a deal by the end of the year, Brits could be treated as citizens of a “unlisted country” when travelling to the EU.
Ms Dos Santos said: "What that means is that for owners to prepare to take their pets abroad they need to start thinking about it now really.
"In all there's a four month lee-way period, so if you are thinking about travelling close to the EU exit date I would be suggesting you speak to your vet relatively soon."
The pet passport scheme will be voided if talks collapse and there is no agreement by December 31.
That means British cats and dogs located in Europe would not be recognised by the EU Pet Passport scheme - even if they have not been chipped and tested for free movement.
Ms Dos Santos said in the case of a no deal Brexit cats, dogs and ferrets will need to have a rabies vaccine before travelling to the EU.
Pets then have to wait 30 days before taking a blood test - and another three months before they can travel freely.
That means if owners want to travel with their fluffy friends in January, they'll have to start the process in August to get them ready to jet off.
The total cost of the rabies jab, blood test and official paperwork could be as much as £200, according to experts.
If Britain is treated as an unlisted country it could mean owners have to go to the vet every time they want to take their pets abroad.
If the EU take a less strict approach to pets and make the UK a "part 1 unlisted country" owners will still need to get them vaccinated, wait 21 days before travelling and reapply for a UK new pet passport - but that will last for the pet's lifetime.
Ms Dos Santos said the third option would mean British pets "will need vaccines and to wait 21 days, but also to get an animal health certificate no more than 10 days before travel.
The coronavirus crisis will also make it even harder for pet owners to get their animals checked quickly.
Ms Dos Santos said: "The challenge will be that the visit has to be with an official vet.
"The profession is still reeling from the effects of Covid - it will take you longer to get an appointment to get through all of these."
DEATH RIDDLEMum-of-four, 37, who left husband for homeless man is found dead
MANDELA HEARTACHNelson Mandela’s daughter Zindzi dies seven years after hero dad’s death
LOCAL LOCKDOWN SPIKEHancock reveals over 100 virus local lockdowns being enforced per WEEK
HOUSE WOWEDThree-bed semi with garden goes on sale - but you'll never guess how much for?
ROOFTOP RUMBLEMoment mass brawl erupts in rooftop bar as revellers hurl tables and chairs
FARM LOCKDOWNCops guard virus-hit farm exit as 73 staff catch bug & 200 told to quarantine
CORONAVIRUS CRISIS - STAY IN THE KNOW
Don't miss the latest news and figures - and essential advice for you and your family.
To receive The Sun’s Coronavirus newsletter in your inbox every tea time, sign up here.
Get Britain’s best-selling newspaper delivered to your smartphone or tablet each day – find out more.