Cruise lines Royal Caribbean and Norwegian said on Wednesday that they will no longer sail to Cuba, joining Carnival Corporation, which announced earlier in the day that it will no longer operate cruises to the island, effective immediately.

The companies’ decision came one day after the Trump administration banned cruises, private yachts and fishing vessels from visiting Cuba, and left many travelers frustrated and confused, especially those currently en route to Havana.

“I’m one of hundreds of very angry passengers aboard a cruise ship in the middle of the Caribbean,” wrote Cindy Hamilton on Twitter. “We all planned this cruise anticipating our stop in Cuba. Very upset!”

The new regulations affect nearly 800,000 bookings that are scheduled or already underway, according to the Cruise Lines International Association, an industry group. These bookings were made under a license issued by the United States government that allowed “people to people” travel to Cuba. This category has been banned by the new regulations.