New EU rules on travelling with pets come into force tomorrow (22 April) that will affect some people in the Channel Islands who take their pet to France.
The issue is for islanders who take their pet away on EU pet passports.
From Wednesday these documents will no longer be considered valid for British residents, including islanders with second homes on the continent.
They will only apply for people whose main residence is in the EU or Switzerland.
Ferry firms are contacting passengers due to travel this week to advise of the change.
The authorities say these pet owners must instead get an Animal Health Certificate from a local vet within 10 days of travelling to the EU.
The certificates cost around £175 or more per pet, and one is needed each time you go abroad.
"All pet owners are strongly advised to check entry requirements with the relevant authority in the destination country before travel."
In a social media post, New Era Veterinary Hospital in Jersey said:
"We understand that several pet owners are going out with their pets with DFDS on Wednesday morning, and several more at the weekend. We strongly advise these owners to contact their vets as soon as possible."

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