Two US Airlines, Silver Airways and Frontier, are terminating their services to Cuba, only some six months after the air ties between the two countries were restored following 50 years of silence, USA Today reported.

Silver Airways (Silver) will be dropping nine flights connecting the US and Cuba by 22nd of April 2017 and its compatriot Frontier will end the Miami-Cuba route on the  4th of June  2017.

The two airlines are blaming overcapacity on their routes. Frontier’s spokesperson, in addition, told USA Today that the operating cost in Havana is ‘exceeding Frontier’s assumptions’.

More airlines say farewell to Cuba

Silver and Frontier are not the only US airlines experiencing operational issues on Cuba-bound routes.

American Airlines announced in December 2016 that they would be cutting frequency of their Miami to Cuba (Holguín, Santa Clara, and Varadero) flights as of the 16th of February 2017. American, however, will still operate a daily flight to each of the three cities.

On the second week of February 2017, the first U.S. airlines to land in Cuba after five decades – JetBlue – announced that it is also reducing its service to Cuba. The New York-based LCC will maintain the existing routes to Cuba, but it will employ smaller aircraft which will be effective on the 3rd of May 2017.

American Airlines announced Thursday they would be cutting three of their Miami to Cuba frequencies on Feb. 16, 2017. The announcement of these cuts comes just days after the airline announced they would be cutting capacity on three other routes from Miami to the island nation.

The overestimated demand on US-Cuba routes is also accused to have been one of the reasons of the cutbacks. Adam Levine-Weinberg at the Motley Fool wrote that the U.S. Department of Transportation (DOT) allocation process also encouraged airlines to "overbid." In other recent route allocation proceedings, the DOT has shown a clear preference for carriers that promise to use bigger aircraft.

There are six US airlines serving the flights connecting USA and Cuba - American Airlines, Delta Air Lines, United Airlines, Frontier Airlines, Silver Airways and JetBlue. With the latest trend on the route, there are only Delta and United which have not cut any service to Cuba.

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