Thomas Cook will stop selling trips to attractions that keep killer whales, the firm has announced.

The operator said its decision not to sell tickets to SeaWorld in Florida and Loro Parque in Tenerife reflects a survey which found 90% of its customers were concerned about animal welfare.

Announcing the decision in a blog , Peter Fankhauser, chief executive of Thomas Cook, said the decision was  not taken lightly.

“From next summer, we will no longer sell any animal attractions that keep orcas in captivity,” he said.

“We have actively engaged with a range of animal welfare specialists in the last 18 months, and taken account of the scientific evidence they have provided.

“We have also taken feedback from our customers, more than 90% of whom told us that it was important that their holiday company takes animal welfare seriously.

“And when so many of our customers are so clear in their view, I could not allow our business to ignore them.

“I am clear about the kind of business that we want to be. That’s why we introduced our animal welfare policy 18 months ago, and that’s why we’ve taken this decision today.”

Fankhauser acknowledged the advances both parks have made amid global criticism following the release of film Blackfish in 2013 and said it would work with them as it exits over the next 12 months.

As a result SeaWorld ended its breeding programme but plans to continue operating shows with its existing orcas for “many years”.

The park said: it would continue to welcome the “millions of UK guests” who visit its parks.

“They have seen first-hand the incredible care we provide all of our animals and learned about how we are protecting and saving species in the wild.”

In a statement, SeaWorld said that it is: “world-renowned and recognised as a global leader for the quality of care it provides the animals in its care, and for its rescue, rehabilitation and conservation efforts on behalf of marine animals and their habitats.’

“SeaWorld Parks & Entertainment has now completed a full animal welfare audit and through that independent auditing process undertaken by Global Spirit Animals In Tourism Limited, SeaWorld Orlando, Discovery Cove and Busch Gardens Tampa Bay achieved 100% of the strict minimum standards required by the travel and tourism industry, as contained within the Association of British Travel Agents (Abta) Global Welfare Guidance for Animals In Tourism.

“Millions of UK guests have visited our parks for fun, education and to help contribute to the protection of marine animals and their habitats. They have seen first-hand the incredible care we provide all of our animals and learned about how we are protecting and saving species in the wild.

“Although we have ended breeding for orcas, the current animals in our care will be with us and our visitors for many years to come. We will continue to welcome the public into our parks for the unmatched experiences we create every day.”