Carnival Cruise Line has notified booked guests and travel advisors that its pause in operations from U.S. ports has been extended through May 31, 2021, according to a press release.

A date for the return of guest cruising operations from U.S. ports has not yet been determined, the company said.

Earlier in February, Carnival began providing more flexible options for guests booked into early summer so that they could cancel their reservation without penalty if they needed or wanted to make other plans. As it has done throughout the pause, Carnival is providing guests on cruises cancelled today the choice of a future cruise credit plus onboard credit package, or a full refund.

“We continue to work on plans to resume operations and are encouraged by the focus to expedite vaccine production and distribution which are having a demonstrated impact on improving public health,” said Christine Duffy, president of Carnival Cruise Line. “We appreciate the support of all of our guests, employees and trade partners who we know are looking forward to our return.”