The brand, which employs 15,000 people, has entered a 90-day consultation process with administrative and managerial employees, as it seeks to turn around a £485.3m pre-tax loss in the previous financial year.
A Thomas Cook spokesman confirmed its marketing department is affected by the announcement. However, it is not believed to impact Mike Hoban, sales, marketing and ecommerce director, who joined the business from Confused.com in November.
As part of the three-year "transformation programme", Thomas Cook will also close 195 of its 1,069 UK high-street stores.
Peter Fankhauser, Thomas Cook UK and Ireland chief executive, said: "Thomas Cook is a much-loved brand that needs to make the proposed changes to secure our future and provide continued employment for many thousands across the UK and better meet the needs of our customers going forward.
"It is essential that we operate with the right number of people as we move forward into the next era for our company."Follow @alex_brownsell