LONDON (AFP) - British holiday firm Thomas Cook will stop selling trips to animal parks which keep captive killer whales, including SeaWorld in Florida and Loro Parque in Tenerife.

"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", chief executive Peter Fankhauser wrote in a blog post.

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

He confirmed that tickets to such attractions will no longer be sold from next summer.

Animal welfare concerns over the treatment of orcas in captivity have been amplified since the critically lauded 2013 documentary Blackfish, which argued that the highly intelligent animals are psychologically traumatised in tourist attractions such as SeaWorld.

Mr Fankhauser said the decision came after an introduction of a new Thomas Cook animal welfare policy which recognises "that customer expectations were changing when it comes to animal attractions" and "the important role tourism has to play during the transition to ending practices that are known to harm animals".

Animal rights campaigners People for the Ethical Treatment of Animals (Peta) have been campaigning for Thomas Cook to drop the holidays for the past 12 months, with 150 protests around Britain.