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
Arkansas has become the first US state in 17 years to carry out back-to-back executions after putting two inmates to death.
Up to three million children risk going hungry over the school holidays, with increasing numbers of families relying on food banks, MPs say.
Tuesday will be a cold and windy day across the British Isles with a mix of sunshine and showers.