KPMG said it was currently “in the process of completing an exchange” with IAG for both Monarch’s summer and winter slots at the airport after the firm won a High Court legal battle to be able to sell off the assets earlier this month.

Monarch’s slots at Gatwick and Luton, which are also due to be auctioned off, were seen as being one of the failed company’s most valuable assets following its demise - worth an estimated £60 million.

The carrier ceased trading on October 2 with 110,000 customers overseas. It operated around 20 slots from Gatwick.

IAG, which also owns Vueling, Aer Lingus and Iberia, reportedly faced competition from low-cost rivals keen to acquire the slots such as easyJet, Wizz Air and Norwegian. IAG said that the Gatwick slots would be "primarily" used for new British Airways flights.

In a statement KPMG partner and joint administrator Blair Nimmo said the sale of Monarch’s Gatwick slots "represented an excellent recovery for creditors".

"Our continuing focus is now on MAL’s [Monarch Airlines Ltd’s] Luton slots, as well as exploring potential rescue opportunities for MAL and its residual assets including its brand and associated licenses," he added.

IAG said in a statement: “IAG can confirm that it is in the process of completing the acquisition of Monarch’s slot portfolio at Gatwick.

“These slots will be used by the group’s airlines, primarily British Airways, enabling them to grow their presence at the airport and launch new destinations and add extra frequencies.”