Special charter service to the United States were allowed from the 1990s, but were required to be operated by travel companies licensed by the U.S. government, largely from Florida. In March 2015, Sun Country Airlines started operating regularly scheduled charter flights from New York during the Cuban Thaw. Regularly scheduled commercial service to and from the United States began again in the fall of 2016, with such airlines as American, Delta, JetBlue and, after January 2017, Alaska, flying to Havana. However, several airlines had dropped, if not cut back, flights to Cuba by late 2017 due in part to President Trump's decision to reimpose stricter travel regulations, therefore partially ending the Cuban Thaw. Several other reasons that the airlines ended the flights were because of weaker-than-expected demand and a paucity of tourist infrastructure.