Luton-based EastJet has reportedly made an approach to buy Monarch Airlines' short-haul business.
Wizz Air are also thought to be interested in either establishing a partnership with Monarch, or purchasing their operation outright.
It's believed that Monarch, who are owned by private equity firm Greybull Capital, have hired professional services company KPMG to help investigate options for selling their short-haul business because they want to focus on long-haul routes instead.
Luton-based Monarch were in dire financial trouble a year ago, but managed to secure a £165 million investment to keep its operating licence with the Civil Aviation Authority.
Monarch currently employs around 2,750 staff and flies to 40 destinations.