HAVANA -- As the U.S. and Cuba begin to normalize relations for the first time in half a century, some Americans are already roaming the streets of Old Havana, attending dance exhibitions and talks on architecture as they take part in scripted cultural tours that can cost more than a decent used car back home.

The U.S. visitors are participants in the highly regulated "people-to-people" travel that President Barack Obama permitted in 2011 in one of his first moves toward detente with Cuba. The program aims to increase interaction with ordinary Cubans without creating uncomfortable images of Americans lounging on beaches in a single-party state. The tours tend to attract people sympathetic to improving ties with President Raul Castro's government.

"It's pre-selected for people who already want there to be change," said Jonathan Anderson, a 33-year-old from Denver on an eight-day excursion that cost $6,000 per person. "People aren't coming here to see how evil Castro is. They are coming here to reinforce ties."

Travel experts said Sunday that the new opening to Cuba that Obama announced four days earlier goes far beyond the 2011 reform and could sharply increase U.S. tourism in the coming years.

Among the changes, Obama directed the Treasury Department to expand the categories of travellers who can go to Cuba without requesting a license from the department first. Soon to be covered by a standing, blanket travel permit are participants in educational activities, the category that covers most people-to-people travel. Experts said that eliminating the licensing requirement could greatly reduce the costs of organized tours by cutting paperwork. It also could, perhaps more importantly, allow huge numbers of Americans to legally travel on their own to Cuba.

In the past, people-to-people travellers could only go to Cuba under a license obtained by a travel company in a time-consuming process followed by lengthy government verification that travellers weren't engaging in inappropriate leisure tourism.

"We can't go to the beach and drink mojitos all day," said Tony Pandola, who was leading Anderson's trip with Global Expeditions of San Francisco, California. "That doesn't have any sort of objective as an educational or cultural exchange."

Now, according to travel experts awaiting regulations expected within weeks, it appears tour companies will be able to head to Cuba and simply give the U.S. government their word that they're engaging in educational travel and not ordinary tourism. Some think the new "general license" travel permits would apply to individuals, allowing people to go on their own.

"As long as with integrity they can say they're going to engage with the Cuban people and learn about Cuba and talk about the United States then they don't have to do anything other than say that's what they're doing," said John McAuliff, executive director of the Fund for Reconciliation and Development, which has organized trips in the past.

The easing of tourism regulations is a gamble for both the U.S. and Cuba.

Obama said Wednesday that people-to-people travel was a way to "empower the Cuban people." At the same time, a U.S. tourism surge could funnel sorely needed cash to a tourism industry run mostly by what Obama described Friday as "a regime that represses its people."

Experts don't expect American tourists to flood Cuba immediately after the new regulations are published. The daunting complexity of the legal details and the possibility, even remote, of fines for violations will probably mean most new travel to Cuba will still go through tour organizers. Those organizers are currently required to do business with state-run travel companies, meaning tour agendas are now almost entirely under the purview of the Cuban government.

People-to-people travel can cost $2,000 to $6,000 per person and tour organizers are supposed to keep the formal itinerary full to meet U.S. regulations. "We can go out and see things but we have to conform to the rules," Anderson said.

General tourism to Cuba is still prohibited by the half-century old trade embargo, and it would take an act of Congress to lift it. But that hasn't stopped many Americans from travelling to Cuba through a third country and keeping quiet about it when they go through immigration and customs upon arrival back in the United States.

The number of U.S. travellers to Cuba has increased steadily each year, from about 245,000 in 2007 to nearly 600,000 last year, according to a report by the U.S.-based Havana Consulting Group. The most recent statistics from Cuba's government show that about 73,500 Americans visited in 2011, but that doesn't include dual citizens who it counts as Cuban.

Tom Popper, president of tour organizer Insight Cuba, said he thinks many new travellers to Cuba will take organized tours because it can be difficult for an individual to organize a trip that meets Treasury Department requirements.

Still, eliminating the license requirement will remove a significant bureaucratic hurdle, according to Popper, whose last application was more than 700 pages long.

"This is such welcome news to us," Popper said.

And the appeal of visiting Cuba goes beyond education to some Americans.

"I'm looking for a warm climate, it's historical obviously and it's also a place that most Americans don't go," said Katja Von Tiesenhausen, a 41-year-old emergency room doctor from Boston, taking part in another tour.