Carnival Corp expects the coronavirus pandemic will cost the company $1bn per month as a result of laying up its entire fleet, providing cruise refunds and paying debt maturities.

The Arnold Donald-led cruise major expects to suspend all 104 ships across nine brands in a "warm layup" with full crew through at least mid-May at a cost of $2m to $3m per month, according to a regulatory filing.

It further forecasts a "prolonged ship layup" with limited crew that will cost $1m per month.

"We will decide whether each vessel in our global fleet will be in a warm ship layup or a prolonged ship layup depending on the circumstances, including the length of pause, which we expect to be extended and may be prolonged," the New York-listed company said.

"We currently estimate the substantial majority of our fleet will be in prolonged ship layup.

"After transitioning to a prolonged pause, we anticipate estimated ongoing ship and administrative operating costs to range from $200m to $300m per month."

Carnival also expects further vessel costs related to sanitising its vessels, defending lawsuits and incurring selling and administrative costs that it is looking to lower significantly.

The company will also have to pay refunds or give credits on $4.7bn in cancelled cruises through 29 February and possibly for customer deposits for other voyages planned through 2021.

Monthly costs will also include principal and interest payments on billions of dollars in credit and loan facilities, including $1.5bn in long-term debt coming due by 30 November.

Further debt expense will consist of $3bn in spent debt maturing in September, $200m per year interest expense on top of interest to be paid out on $5.75bn in debt attained in March.