Dnata Travel Group brands are to start processing refunds on cancelled holidays and flights for customers who have requested them.
Payments will begin to be made from the week starting May 4 for those who were due to depart week from March 22.
The agreement covers the trade-only brands Gold Medal and Travel 2 and consumer travel firms Travel Republic, Travelbag, Netflights and Sunmaster.
Refunds are being processed in a strict departure date order on a rolling weekly basis, according to the Emirates-owned travel organisation.
The brands have begun to communicate expected payment dates to their customers and travel agents.
Customers who accepted a refund credit note can “rest assured those remain valid as per the terms and conditions”.
Dnata Travel Group chief executive John Bevan said: “This has been an exceptionally challenging period for our organisation.
“I would like to apologise to our clients and travel partners and thank them for their patience, and praise our people for their incredible efforts behind the scenes while we have worked to re-set our organisation to cope with the crisis.
“We have been working extremely hard to bring customers home, and transitioning our team and processes from handling large volumes of new bookings to a sudden mass of cancellations.
“Never has a crisis in the history of our industry reversed entire organisations in a matter of days, and never have bookings literally dried up.”
He added: “We’re now in a position to make these overdue payments and start looking to the future.
“The significant volume of refund queries and requests we have received means that it will take time to work through the backlog, so we want to thank all of our customers and agent partners in advance for their continued forbearance.”
Speaking on ITV’s News at 6.30pm on Wednesday as it reported on the refunds controversy, Bevan said: “The whole thing amalgamates to something you cannot be prepared for.
“It’s a choice between having really good travel businesses survive and get through this with a little bit a patience or face close down.”