Marella Cruises is further extending the cancellation of sailings until September 30.
The Tui UK & Ireland line’s only ship sailing this summer will be Marella Explorer from Corfu from October 2.
The extension of the cancellations was blamed on on-going travel restrictions in the wake of the Covid-19 pandemic.
All cruises had previously been cancelled last month until at least August 27.
Passengers whose bookings are impacted by the changes will receive a refund credit and up to 10% incentive of the total value of their booking.
Alternatively, they can request a cash refund via an online form on the Tui website.
The company added: “Due to the on-going uncertainty customers with bookings due to depart in October can amend their cruise for free before the 31 July to any other holiday on sale until October 2021.”