Norwegian Cruise Line Holdings and Viking have joined rivals in extending the suspension of cruises.
The parent company of Norwegian Cruise Line, Oceania Cruises and Regent Seven Seas Cruises will not run any sailings until at least May 10.
Departures had previously been suspended until April 12.
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The extended suspension “contributes to the global efforts to contain the spread of Covid-19, which has also resulted in travel restrictions and continued uncertainty regarding worldwide port closures and availability,” the group said.
Viking, the first line to temporarily suspend operations of its river and ocean cruises due to coronavirus, has extended its suspension of operations from April 30 until June 30.
Chairman Torstein Hagen said: “We are using this period of non-operation as a time for additional training and initiatives to ensure we have the safest and healthiest fleet in the industry.
“As a private company we do not have to worry about quarterly profit expectations – and that flexibility allows us the ability to do what is best for our guests and our employees.”
Sister Carnival Corporation cruise lines – Carnival Cruise Line, Holland America Line and Seabourn – also announced further delays.
MSC Cruises extended the halting of all its ships globally from April 30 to May 29.
NCLH president and chief executive Frank Del Rio said: “With Covid-19 continuing to have a significant impact on communities throughout the world, we are extending our temporary suspension of cruise voyages across our three brands through May 10th.
“While we understand this disruption may inconvenience our loyal guests and valued travel partners, we are committed first and foremost to protecting the safety, security and well-being of our guests, crew, and the communities we visit.
“We appreciate their continued understanding as we navigate through these unprecedented times and do our part to help global efforts to contain this pandemic.”
Passengers booked to sail between March 13 and May 10 on any of the group’s 28 ships are being asked to contact their travel agent or the individual cruise line for more information.