* Department may lack authority to strike deal - senators
* Similar centers at 15 locations in Canada, elsewhere
* UAE would pay up to 80 percent of the operating costs (Adds U.S. Customs comment, byline)
By Doug Palmer
WASHINGTON, May 10 An agreement to extend U.S. customs pre-clearance operations to Abu Dhabi International Airport in the United Arab Emirates has drawn questions and criticism from nearly a dozen senators.
Pre-clearance allows U.S.-bound passengers to get advance approval to enter the United States from locations in airports outside the country.
"We question whether the Department (of Homeland Security) has the authorization to enter into such an agreement, and we are concerned by the precedent set by the Department's action," 11 senators said in a letter to Homeland Security Secretary Janet Napolitano, dated on Wednesday.
The United States has pre-clearance centers at 15 locations in Canada, Aruba, Bermuda, the Bahamas and Ireland, according to the U.S. Customs and Border Protection (CBP) website.
The arrangements with Canada and the resort islands date back to the 1950s and 1960s, and the arrangement with Ireland to the 1980s, with modifications over time.
"The Pre-clearance Agreement with the UAE will enhance our aviation security by allowing U.S. security officials to screen passengers before they board flights bound for the United States," Jenny Burke, a spokeswoman for the CBP said.
The pact underscores "our commitment to protecting the safety and security of our citizens while also streamlining legitimate travel and commerce," she said.
Airlines for America, the main U.S. industry group, has complained the agreement will divert U.S. customs resources to the UAE when they could be better used to ease congestion at domestic airports.
"Reducing wait times at U.S. airports should be a top priority of DHS and CBP, not using U.S. tax dollars to benefit a foreign government, particularly when wait times at U.S. points of entry continue to be excessive," group President Nicholas Calio said in a statement.
The senators said their understanding was that the UAE will pay up to 80 percent of the cost of operating the facility at Abu Dhabi's airport, which is the hub for UAE-owned Etihad Airways.
The airport "is not served by any air carrier based in the United States," their letter said.
"By establishing foreign-funded pre-clearance operations at an airport with so little traffic bound for the United States, we question whether the Department is choosing pre-clearance locations based on risk or a pay-to-play process," they said.
They pressed Napolitano to "clarify the rationale for allowing a foreign government or entity to pay for core security functions."
A U.S. official said the reimbursement provision of the pact would be used to improve CBP operations, leading to shorter wait times at U.S. points of entry.
The two sides have agreed on the outlines of the program, but details needed to be worked out before pre-clearance can start in the UAE, the official said. (Reporting by Doug Palmer; Editing by Philip Barbara and Xavier Briand)