NEW YORK (CBSNewYork) — The U.S. transportation secretary is threatening to take action against Kuwait Airways if it continues to discriminate against Israelis trying to fly between the United States and United Kingdom.

The airline has reportedly denied New York-to-London tickets to at least two people with Israeli passports. Kuwait recognizes an Arab League boycott of Israel and Israeli businesses.

But U.S. Transportation Secretary Anthony Foxx issued a statement Tuesday saying, “Discrimination by Kuwait Airways against Israeli passengers flying between New York and London is both unwarranted and unacceptable, and must come to an end now.

“If the airline does not quickly and voluntarily alter its behavior, (the DOT) is prepared to use all tools at its disposal to protect the civil rights of passengers.”

The DOT would not say specifically what type of action it might take, but some New York City Council members have urged the agency to revoke the airline’s permit to fly in the United States.

Not selling to Israeli customers violates U.S. laws prohibiting discrimination and boycotts targeting Israelis.