All Fred Olsen Cruise Lines sailings have been cancelled until the end of June.
The company had been due to resume sailing on May 22, with the extension affecting 14 sailings.
The latest pause in operations come “in light of the current restrictions in England as a result of the pandemic,” the line said.
Affected passengers will be given a number of options, including a refund or an additional future cruise credit.
Managing director Peter Deer said: “We are constantly reviewing our back in service dates in line with the latest government guidance, and working closely with Clia and other industry bodies towards a return to sailing.
“This extra time allows us the opportunity to fully understand how the roll-out in the vaccine affects the procedures we operate on board and ashore.
“We know that our guests are missing cruising, as indeed are we, and we can’t wait to welcome them all back on board when the time is right.”