Carnival Corp. has delayed a return to sea for its Princess and Cunard cruise lines, cancelling several sailings scheduled for 2021 as the coronavirus pandemic rages on.

Princess and Cunard are both headquartered in Santa Clarita.

Cunard Line will extend its pause in operations through March 25, 2021. The company previously said it would resume cruising in November.

Princess announced the cancellation of 29 cruises on two ships scheduled for early 2021 “due to limitations with border and port access … and the continued uncertainty of airline travel,” the company said in a statement.

Cancelled are world cruises on the Island Princess and South American cruises on the Pacific Princess. The ships will resume operations as scheduled in April 2021 at the earliest.

“We share in the disappointment of this cancellation for guests of our world cruises because it’s a pinnacle cruise vacation experience,” Princess Cruises President Jan Swartz said in a statement.

Guests whose bookings on Cunard or Princess ships have been cancelled will receive refundable future cruise credit.

The delay affects all three of Cunard’s ships. With the new schedule, the Queen Elizabeth is slated to return March 25, the Queen Mary 2 on April 18 and the Queen Victoria on May 16.

Additionally, Cunard has cancelled all of the Queen Elizabeth’s scheduled cruises through December 2021, citing “ongoing uncertainty over the re-opening of ports.” That includes planned sailings around Australia, Japan and Alaska. The Queen Elizabeth’s cancelled voyages will be replaced with “a program of shorter duration European vacations from Southampton and a series of Mediterranean voyages sailing from Barcelona, all of which will be available to book from September 29, 2020,” according to Cunard’s website.

Also affected are Queen Mary 2 sailings scheduled for between January 3 and April 3, 2022, including a voyage to South America, which will be replaced with a 118-night round trip to Australia via the Suez Canal – a way of making up for two previously cancelled World Voyage cruises.

Parent company Carnival Corp. is a defendant in several lawsuits alleging the company failed to take proper safety precautions in managing coronavirus outbreaks on two of its ships, the Diamond Princess and the Grand Princess, which saw a combined 800 coronavirus cases and 10 deaths in March and April, according to the CDC.