By Jeffrey Dastin

April 30 (Reuters) - More than 250 members of Congress have signed a letter urging the U.S. departments of state and transportation to seek consultations with Qatar and the United Arab Emirates over subsidies the states have allegedly given Gulf airlines.

The letter, sent Thursday, adds to political pressure on the Obama administration since three U.S. airlines first alleged in January that Emirates airline, Etihad Airways and Qatar Airways have received more than $40 billion in subsidies in the last decade. U.S. airlines say this has allowed the Gulf carriers to drive down ticket prices and push competitors out of key markets.

"Failure to address these practices will lead to significant job losses in the United States and set a dangerous precedent that could lead to further harm to the U.S. airline industry and the broader U.S. economy," the letter said.

The Gulf carriers have denied the subsidy allegations and said U.S. airlines' service is not competitive and has caused them to lose market share. The carriers say they have supported thousands of U.S. jobs by buying U.S.-manufactured airplanes and by flying thousands of travelers to the country, helping the U.S. economy.

The Obama administration has solicited comments from interested parties and expects to begin reviewing them by the end of May.

It has said it is seriously considering the competition concerns raised by U.S. airlines but that it also remains committed to the Open Skies policy that authorizes flights to and from foreign countries.

(Reporting By Jeffrey Dastin in New York; Editing by Ken Wills)