FLAGSTAFF, Ariz. (AP) – Navajo President Russell Begaye vetoed legislation Monday to negotiate a $20 million loan package for new aircraft, saying the details of a possible purchase were scarce.

Begaye said concerns his office raised months ago, including justification for the loan and the funding source to repay it, never were addressed.

“This administration is not going to support efforts blindfolded,” Begaye wrote in a veto message to Navajo Nation Council Speaker LoRenzo Bates.

The tribe has three Beechcraft King Air turboprop planes that tribal offices can use for travel across the country, although priority is given to the president, vice president and council speaker.

The bill would have allowed tribal officials to negotiate a loan to replace those planes with new aircraft – possibly jets.

The sponsor of the loan package, Davis Filfred, said the current aircraft will be grounded next year because it’s too costly to keep overhauling the engines. He maintained Monday that new aircraft is needed for tribal officials to conduct business. The vast 27,000 square-mile reservation does not have commercial airline service.

“We’ll have to regroup and talk about it some more and we’ll go from there,” Filfred said.

Tribal members raised concerns about the need for aircraft on the country’s largest American Indian reservation where most roads are unpaved, unemployment hovers around 50 percent, and running water and electricity can be considered luxuries. Some questioned why tribal leaders couldn’t drive to the nearest commercial airport.

The tribe’s current planes were put into service in the late 1980s and early 1990s.

Begaye called for a feasibility study that would outline specifics for new aircraft and associated expenses, including maintenance and supplies. The tribal controller’s office has said the general fund would be the most likely source to service the loan, but the exact source wasn’t identified in the legislation. Tribal trust funds, money from a $554 million settlement and the rainy day fund were excluded as forms of repayment.

Begaye also questioned whether the legislation could go forward without a two-thirds vote of the 24-member Tribal Council needed to waive the tribe’s right not to be sued. Lawmakers approved the bill 13-5. Begaye said it did not include an “expressed” waiver of sovereign immunity.