The group commissioned animal welfare specialists Global Spirit to audit a cross section of the attractions it sells against the Abta Global Welfare Guidance for Animals in Tourism, which Cook said were “widely accepted as the most stretching guidelines in the world”.

Writing in a comment piece today Peter Fankhauser said he was “disappointed, not only with the lack of engagement from a number of suppliers, but also the findings of the audit”.

Cook has now insisted that if an attraction is not found to be compliant with the Abta Global Welfare Guidance for Animals in Tourism, then it won’t sell it.

As part of the move, Cook said that from January 1 2017, Global Spirit would conduct a full audit of excursions offered by the operator, and that attractions would receive no notice of the audit.

It added that attractions would be expected to comply and provide access to relevant materials, and any failure to do so will see the attraction immediately removed from sale.

“If the audit shows an attraction is not compliant, they will have three months to show they have resolved any issues. We will work with the supplier to improve conditions over this period. If they don’t improve to the required standard then we will put the attraction on stop-sale and end all promotion to that attraction,” it added.

“Even if an attraction is taken off sale, we will continue to provide assistance to suppliers to help them to meet the required standards. Decisions to put an excursion back on sale if it does meet compliance after the three-month deadline will be taken on a case-by-case basis.”

Will Travers, chief executive and president of the Born Free Foundation praised the move. “Thomas Cook’s decision to lead the travel industry away from the exploitation of wild animals in captivity for entertainment purposes, towards a future where their welfare needs are respected and tourism becomes a driver for conservation and environmental protection, is a vision I and millions of others wholeheartedly support.

“Thomas Cook and Born Free are charting new territory where an extraordinary future beckons, one based on respect and compassion. Together we will defend the principle that wild animals should be free, and we commit ourselves to their protection and the conservation of the natural world.”