The world’s four largest cruise lines have cancelled their December itineraries in the US, extending their pause in operations into 2021 following the CDC’s withdrawal of its No Sail Order at the end of November.

The move by Carnival Corporation, Royal Caribbean, Norwegian Cruise Line and MSC Cruises may appear contradictory, as the CDC’s move to rescind the No Sail Order clears the way for a gradual resumption of cruises in the United States.

Carnival has cancelled all US cruises through December 31, 2020.

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However, getting a laid-up cruise ship back into service can take up to a month, and the CDC’s conditional sailing order, which will assess every cruise line individually, includes strict requirements that will delay the reintroduction of ships further.

One of the biggest factors in the delay will be the requirements for ships to sail several test voyages to ensure that new health and safety protocols work as intended in preventing the spread of COVID-19.

The Centres for Disease Control and Prevention (CDC) last week dropped its No Sail Order for cruise ships.

As a result, Carnival Corporation said all its North American cruise brands (Carnival Cruise Line, Princess Cruises, Seabourn and Holland America) will extend their pause in operations until December 31, 2020.

” Our highest responsibility and top priorities are always compliance, protecting the environment, and the health, safety and well-being of our guests, the people in communities we touch, our crew and shoreside employees,” said Arnold Donald, CEO of Carnival Corporation.

” We continue to work with the U.S. Centers for Disease Control and Prevention, and global government and public health authorities, as well as top medical and science experts around the globe, on a comprehensive plan for the eventual restart of cruising in North America,” he added.

“With their collective guidance, we have developed and continue to update our enhanced health and safety protocols that are in the best interest of our guests, crew and overall public health,” Donald said.

Royal Caribbean has cancelled its entire US program for December.

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Royal Caribbean has also cancelled its entire December cruise program, apart from a planned resumption of cruises in December with the Quantum of the Seas from Singapore, which will embark Singaporean residents only.

“We plan to utilize this time to thoroughly train our staff and crew on our new health and safety protocols, while also conducting a number of trial sailings to stress-test these measures in real-world conditions,” the company said, in a statement.

NCL has cancelled cruises aboard all three of its brands until the end of the year.

Norwegian Cruise Line Holdings has cancelled all December cruises scheduled for its three cruise line brands (Norwegian Cruise Line, Oceania Cruises and Regent Seven Seas Cruises).

The company said it will continue to work in tandem with global government and public health authorities and its Healthy Sail Panel expert advisors to take all necessary measures to protect its guests, crew and the communities visited.

MSC Bellissima in Dubai.

MSC Cruises, the world’s largest independent cruise line, has cancelled its scheduled US cruise itineraries until December 31, 2020, cancelling voyages aboard MSC Seaside from Port Canaveral, and MSC Meraviglia and MSC Armonia from PortMiami.

MSC Cruises will continue to sail its resumed cruise program out of Italy, while Carnival’s European brands Costa Cruises and AIDA Cruises will also continue to sail their limited resumption itineraries in the Mediterranean.