The Transport Salaried Staffs Association, which represents Thomas Cook employees, said it was "shocked and angry" at the scale of the job losses.
General secretary Manuel Cortes said: "This constant policy of slash and burn, with the axing of one in four stores and the loss of jobs, is simply self-defeating.
"The company needs new products if it to come to come to terms with the age of the internet and prosper in the 21st century.
"That is the only way to stop this spiral of decline which repeated bad management decisions over the past five years has led them."
More top news
Donald Trump is set to be sworn in as the 45th President of the United States but major questions still remain over his team.
Ana-Alecia Ayala became an internet sensation for her video showing her dancing and laughing through intensive chemo treatment.
In a week that has lurched from the bizarre to the surreal, we are now just a day away from one of the great rituals of American democracy.