United Airlines' 1st Houston-Havana flight departs Saturday

Balloons in the shape of the airport code for Jose Marti Havana Airport are displayed on a window overlooking planes, including United Flight 1502, left, the first direct passenger flight from Newark Liberty International Airport to Havana, Cuba, Tuesday, Nov. 29, 2016, in Newark, N.J. Commercial flights between the United States and Cuba resumed several months ago as relations between the two countries gradually improved under President Barack Obama. (AP Photo/Julio Cortez) less Balloons in the shape of the airport code for Jose Marti Havana Airport are displayed on a window overlooking planes, including United Flight 1502, left, the first direct passenger flight from Newark Liberty ... more Photo: Julio Cortez, Associated Press Photo: Julio Cortez, Associated Press Image 1 of / 5 Caption Close United Airlines' 1st Houston-Havana flight departs Saturday 1 / 5 Back to Gallery

United Airlines' inaugural flight from Houston to Havana is scheduled to leave Bush Intercontinental Airport at 10:23 a.m. Saturday, a local indicator of thawed relations between the two countries.

Houston is United's gateway to Latin America and the Caribbean with 91 daily nonstop flights to 52 destinations. The Cuba route allows travelers from 20 other markets across the Central and Western U.S. to reach Havana with just one connection.

"Applications were heavily weighted toward South Florida," said Steve Morrissey, United's vice president of regulatory and policy. "We know that there's demand for this service from across the country."

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Re-establishing scheduled commercial flights for the first time in more than 50 years was part of President Barack Obama's efforts to normalize relations with the island nation.

In February, officials from the U.S. and Cuban governments signed an agreement that allows U.S. carriers to operate 110 daily round-trip flights to Cuba. This breaks down to 20 daily round-trip flights between the U.S. and Havana, and 10 daily round-trip flights between the U.S. and each of Cuba's nine other international airports.

In addition to the Saturday-only service from Houston, United began offering daily nonstop flights between New Jersey's Newark Liberty International Airport and Havana on Tuesday.

Yet a Tweet from President-elect Donald Trump has created concern that his administration might roll back Obama's efforts to ease relations with Cuba.

"If Cuba is unwilling to make a better deal for the Cuban people, the Cuban/American people and the U.S. as a whole, I will terminate deal," Trump Tweeted on Monday.

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Morrissey said the airline won't speculate about the future. It is focused on launching and growing its two routes to Havana, he said.

"As for what comes next, we'll focus on that when we need to and if we need to," he said.

In addition to United, the following airlines received approval to fly to Havana: Alaska Airlines, American Airlines, Delta Air Lines, Frontier Airlines, JetBlue Airways, Southwest Airlines and Spirit Airlines. They will fly to Havana from Atlanta; Charlotte, N.C.; Los Angeles; Miami; Newark; New York City; and Orlando, Tampa and Fort Lauderdale, Fla..

Southwest Airlines, United's main competitor in Houston, did not apply for Houston-Cuba routes.

Outside of Havana, six domestic airlines were approved to fly to other Cuban cities. They will depart from Miami, Fort Lauderdale, Chicago, Minneapolis/St. Paul and Philadelphia to Camagüey, Cayo Coco, Cayo Largo, Cienfuegos, Holguín, Manzanillo, Matanzas, Santa Clara and Santiago de Cuba.

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