P&O Cruises and Cunard are extending the suspension of operations for the third time.
All sailings are now cancelled up until July 31 as a result of the continued impact of Covid-19.
Cunard has also dropped its entire Alaska summer season by the ship Queen Elizabeth until September 8.
Cruises by both UK brands were first suspended in mid-March and then again on March 30.
P&O Cruises president Paul Ludlow said: “With the current lockdown in place and government guidelines around the world advising against travel it is necessary to extend the pause in our operations for all sailings up to and including July 31, 2020.
“We are so sorry not to be able to give our guests amazing holidays at the moment, but we will do so as soon as global guidelines will allow. Unfortunately these dates also include the much anticipated Ionafest and we are looking to re-schedule that as soon as possible.
“In the meantime, pending more clarity on the longer term impact of Covid-19 and timing on the world’s return to normality, we are considering the evolving advice as well as potential restrictions in ports of call as we look at how and when we phase our ships back into service.”
He added: “We are working hard to make sure that a holiday with P&O Cruises adheres to relevant measures and guidelines to protect everyone on board without compromising our guests’ enjoyment and experience.
“These new stringent measures will be in place as soon as we reintroduce our ships and we will all get used to them in the same way as we got used to airline hand luggage restrictions.
“They will become the new normal and they will give our guests and crew reassurance and peace of mind.”
Passengers booked up to and including July 31 this year will automatically receive a 125% future cruise credit for sailings until March 2022 based on bookings to be made before the end of December 2021.
Ludlow said: “I am pleased to say that in order to give our guests maximum flexibility FCCs can now be used against a second cabin so guests may bring friends or family or else they can upgrade an existing booking.
“In addition and following feedback, guests can also now gift or transfer the FCC by simply contacting either their travel agent or us, if they booked direct.
“We are seeing strong demand for 2021 and guests looking for a specific date, itinerary or ship should book early as there is limited availability.”
Cunard president Simon Palethorpe said: “These are extraordinary times and this global outbreak continues to challenge Cunard and the travel industry as a whole.
“We would love nothing more than to bring our fleet back in to service, and give our guests the holidays they deserve and long for, but with the lockdowns and travel restrictions in place around the world, this is simply not possible at this time.
“We have been sailing for 180 years and we look forward to many more.
“We will get through these tough times together and look forward to welcoming our guests back on board again when the time is right.”
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