NEW YORK — A U.S.-based organization on Friday canceled people-to-people trips to Cuba that would have transported U.S. citizens there by ship.

Road Scholar canceled the programs after receiving an amended copy of its people-to-people license from the U.S. Treasury Department specifically excluding travel to Cuba "aboard a vessel."

"Travel to and from Cuba, whether originating or terminating in the United States or a third country, may not be aboard a vessel," stated a provision written into the amended license, which Road Scholar received a copy of on Thursday.

Road Scholar, based in Boston, had previously announced trips from Jamaica and Miami with stops in Havana and other parts of Cuba.

Most travel by U.S. citizens to Cuba is outlawed, but tens of thousands of Americans now visit the island legally each year on people-to-people tours, which are licensed by the U.S. Treasury Department. People-to-people trips must have educational and cultural exchange itineraries in order to be approved by the U.S. government.

Typically people-to-people tours fly from U.S. airports to Havana on chartered planes.

In originally announcing the tour July 18, Road Scholar's director of international programs, Yves Marceau, had said it was his understanding that "nothing in the regulations or guidelines" precluded traveling by ship on a people-to-people tour.

Marceau said Friday that "as a result of this new information, we withdrew" the three ocean voyages to Cuba.

Road Scholar, a not-for-profit educational organization that offers guided trips to many destinations, continues to offer land-based people-to-people tours that fly in to Cuba.