Norwegian Cruise Line Holdings sued Florida on Tuesday, accusing the state of preventing it from “safely and soundly” resuming trips by prohibiting the cruise line from requiring customers to be vaccinated against Covid. The cruise operator plans to restart cruises out of the US in August with a 100% vaccination policy

The lawsuit, actually directed against surgeon general Scott Rivkees, the state official who has authority to enforce the ban, is the latest challenge in an ongoing fight against the Florida law, approved in May, to forbid businesses from requiring proof of Covid-19 vaccination. Under that state law, businesses that force customers to provide proof of vaccination could face fines of up to US $5,000 per violation.

Cruise operators have been working to satisfy guidelines set by the Centers for Disease Control and Prevention. Committing to a 95% vaccination rate for crew and passengers is one way for cruise operators to get the green light from the agency, the CDC said.

In its complaint, Norwegian said the potential spread of the highly contagious Delta variant is another driver of its decision to require full Covid-19 vaccinations.

As reported in the Wall Street Journal, Norwegian “argued that restricting the flow of information—in this case, vaccine documentation—affects freedom of speech protected by the First Amendment.

“It also said Florida’s ban disrupts the flow of interstate and international commerce, in violation of a clause in the US Constitution that gives Congress the sole authority to regulate interstate commerce. Those two arguments could position Norwegian well in its case, said Lawrence Gostin, a professor of global health law at Georgetown University.”

In its lawsuit, Norwegian said it was forced to sue ,“as a last resort.”

A federal judge sided with Florida last month in the state’s lawsuit over the federal government’s cruise-industry restrictions. The judge granted the state’s request for a preliminary injunction barring the CDC from enforcing a conditional-sailing order the agency put in place in October 2020. The CDC asked the district court to stay the preliminary injunction, a motion the court later denied. The agency also asked an appeals court to put the ruling on hold.

Norwegian Chief Executive Frank Del Rio, said the company won’t be able to sail in Florida as planned if it must comply with the proof-of-vaccine ban. The cancellation of itineraries for the Norwegian Gem, which will depart from Miami, could result in about US $4 million in lost revenue per seven-day cruise, Del Rio said.

“If we do not abandon our Florida operations entirely, then NCLH will have to revise its operations in ways that are costlier, less safe, less appealing for our passenger base, less likely to meet our commitments to [the] CDC, and are beneath our brand and the quality of experience passengers have come to expect from NCLH,” Del Rio said

Meanwhile, Royal Caribbean Group, while not requiring passengers to be vaccinated does recommend vaccinations. Unvaccinated passengers are subject to additional costs and restrictions the cruise line said, and one of its cruise brands requires unvaccinated guests 12 and older departing from Florida to buy travel insurance.

Carnival Cruise Line also requires travel insurance for unvaccinated guests on cruises leaving from Florida starting July 31.

The cruise industry was devastated by the pandemic, with capacity falling 80 percent last year compared with 2019. The three major cruise companies — Carnival Corp., Royal Caribbean and Norwegian — have lost a combined US $900 million each month since March 2020, according to a recent report by Moody’s, the credit rating firm.