Carnival got official approval to send its first cruise ship to Cuba from the United States in half a century, the leisure travel giant said Monday, as President Barack Obama made a landmark visit to Havana.

The cruise line will send its 704-passenger MV Adonia to Cuba through its new brand Fathom starting May 1.

Carnival, in hailing its "historic inaugural sailing," said it will be the first cruise line to sail that itinerary.

Cuban authorities have now followed Washington in giving the green light to run the service, sailing from Miami, to Cuba, where it will have three approved stops: Havana, Cienfuegos and Santiago de Cuba.

"We are excited about Cuban approval and are ready to take travelers there through an extraordinary guest experience on the beautiful MV Adonia," said Carnival CEO Arnold Donald.

"This is a historic opportunity, and we know there is pent-up demand amongst Americans who want to experience Cuba."

Since US sanctions regulations currently only allow Americans to visit Cuba on educational or social outreach grounds, not as normal tourists, the vessel offers Cuban-themed enrichment programming.

Seven-day itineraries, available at fathom.org, cost at least $1,800.

A majority of Americans back restoring diplomatic ties with communist-run Cuba, a poll found, just as Obama met his counterpart Raul Castro in Havana.

Six in 10 Americans say restoring diplomacy with Cuba is mostly good for the US and 52 percent approve of Obama's handling of relations with the island, said a CBS News/New York Times poll.

However, there are more doubts over what impact it will have on Cuba politically, with half the respondents saying it will make no difference.