Diaz spoke as Cuba's annual tourism convention unfolded at the colonial-era Morro Cabanas fortress overlooking Havana Bay, where talk among officials and tour operators centered on whether the gathering would be the last without a large American presence.

Legislation lifting all travel restrictions on U.S. citizens traveling to Cuba was introduced in Congress just over a month ago, and with a slight thaw in U.S.-Cuba relations under way, is given a good chance of passing.

Cuba has been mostly off-limits to Americans since the U.S. imposed a trade embargo against the communist-led island three years after Fidel Castro took power in a 1959 revolution.

Tour operators from more than 50 countries at the convention dubbed the prospect of open travel from the United States "the American Tsunami" and said it was just a matter of time.

"You know what, I love Americans. Go Obama. Cuba will still be Cuba, the same place with a few Americans added. It's just like adding another spice to the stew," said Richard, a Canadian tour operator who did not want to give his full name.

Cuban officials appeared relaxed about the prospect of the Americans arriving, with one saying "there is no reason to make it a big deal now. They could come in three months or three years."

"I do not expect any tsunami. What's certain is that there will be a convention in 2010, with or without the Americans," Diaz said.

"If they come, too, that's fine. It will simply mean we are going back to normal where all markets are open," he said, adding inquiries from U.S. tour operators had increased significantly.

The Obama administration denied licenses to U.S. tour operators seeking to attend this year's convention, according to John McAuliff of the New York-based Fund for Reconciliation and Development.

"We could have brought 100 operators here," he said. "Next year we will, and if all restrictions are lifted there will be hundreds, maybe even a special event."

(Editing by Jeff Franks and Doina Chiacu)