Kuwait Airways has canceled its flights from New York's JFK airport to London Heathrow after the U.S. Department of Transportation found the airline was illegally discriminating against Israelis and refusing to let them fly on its flights, and demanded it stop, USA Today reported Tuesday.

Canceling its flights to America, effective as of Tuesday, was the airline's response to an order to comply with U.S. antidiscrimination law issued by the Department of Transportation on September 30. "Today, Kuwait Airways informed the U.S. Department of Transportation that they will be eliminating service between JFK and London Heathrow," USA Today quoted Namrata Kolachalam, a department spokeswoman as saying.

The story began in 2013 when an Israeli citizen Eldad Gatt tried to book a flight from New York to London on Kuwait Airways, but the airline's online booking system did not allow him to buy the ticket because it does not allow entering information on Israeli passports. He had originally booked the flight through the Priceline website, but was unable to actually book the ticket with the airline. Gatt filed an official discrimination complaint with the department.

At first the Department of Transportation ruled against Gatt, but after Israel appealed the decision the department reversed its decision. In an official letter to the airline, the department ordered it to “cease and desist from refusing to transport Israeli citizens between the U.S. and any third country where they are allowed to disembark.”

Failure to comply with the letter will leave the department with "no choice but to pursue further administrative and/or judicial action,” wrote Blane Workie, the department’s assistant general counsel for enforcement. Kuwait Airways was given 15 days to comply with the law.

Refusing to sell tickets to Israelis is a breach of U.S. law, Transportation Secretary Anthony Foxx said a few weeks earlier. “If the airline does not quickly and voluntarily alter its behavior, [the federal Department of Transportation] is prepared to use all tools at its disposal to protect the civil rights of passengers,” he said.

Kuwait Airways said it had refused to sell a ticket to Gatt to avoid running afoul of Kuwaiti law, which prohibits its citizens from entering "into an agreement, personally or indirectly, with entities or persons residing in Israel, or with Israeli citizenship.”

The Washington lawyer representing the airline said U.S. law does not authorize the department to enforce its consumer-protection provisions against Kuwait Airways, which "cannot lawfully comply with the terms" required by the department.

The airline filed suit in federal court in Washington saying its policy "isn't discriminatory because it will sell tickets to passengers regardless of race, national origin or religion – so long as they hold a passport valid in Kuwait," and asking to be allowed to continue to fly to the United States. So far the airline has not withdrawn its suit, and if it wins in court the airline could resume flights to America.

There has been at least one other such complaint against the airline and a discrimination suit has been filed against it by another Israeli. Iris Eliazarov, 26, who came to the United States when she was 11 and has a Green Card, was barred from the Nov. 1 Kuwait Airways flight from John F. Kennedy Airport in New York to London. Her husband, David Nektalov, a U.S. citizen, was allowed to board the flight.

The airline’s attorney said the suit has no merit because the policy is based on citizenship, not religion. He said that a Muslim with an Israeli passport also would not be allowed on the plane.

Kuwait Airways received approval to fly to the United States in 2011. It is not clear whether other airlines from Arab countries will be affected too, though both Etihad and Emirates from the United Arab Emirates say they fly many Israelis every year - just not to countries where they will not be allowed in. Saudi Arabian Airlines may be next in the sights of the Department of Transportation.

A number of U.S. senators, including Charles Schumer of New York and Richard Blumenthal of Connecticut, have taken up the cause in the past, demanding the Department of Transportation fine the airlines involved, enforce the law and conduct an investigation.