Monarch is believed to be one of the bidders looking to buy Neilson from Thomas Cook.
But the airline is expected to face competition from a number of private equity investors, reports the Sunday Times.
Reports in February suggested Thomas Cook chief executive Harriet Green was to sell off the ski and sailing specialist business and Gold Medal Travel following a review to reduce debt at the tour operator, see previous story.
Analysts predict the company could raise up to £150 million from disposals.
