Hotels.com has parted ways with Crispin Porter & Bogusky London and put its ad account up for review.
CP&B London has worked with the hotel-booking platform since 2015 and was responsible for introducing the Captain Obvious brand character.
Hotels.com is looking for an agency to help the brand get ready for customers as lockdown restrictions around coronavirus begin to ease around the world.
Last week, the government published a list of countries that those from England can visit and will not need to self-isolate for 14 days on their arrival or return. This includes France, Greece and Spain.
The travel industry has faced financial turmoil over recent months as the Covid-19 outbreak took hold. Barry Diller, chairman of Hotels.com owner Expedia Group, told CNBC in April that the company is unlikely to spend $1bn on advertising this year. The group usually spends about $5bn.
A spokesperson for CP&B London said: "Hotels.com has decided to review their current marketing set-up to ensure it is fit for purpose for a post-Covid-19 travel-industry environment. They invited CP&B London to be part of the review, but we have mutually agreed that CP&B London will not participate.
"We remain extremely proud of the award-winning work we have done for this fantastic client and wish them well."
In October 2019, Hotels.com teamed up with bathroom fragrance maker Poo-Pourri for the "#FirstPooWithBoo" TV campaign.