American Indian tribes are pressing to move gambling operations closer to cities where customers live, but Sen. John McCain is demanding that the Interior Department create a procedure to help decide when tribes can open off-reservation casinos.

The requests from tribes are decided under exceptions to the 17-year-old Indian Gaming Regulatory Act. Off-reservation casino plans have spurred fights over gambling in communities from Washington state to Michigan, but the Interior Department has yet to finalize regulations clarifying how it carries out the law, a department official said at a hearing Wednesday.

"It really is unacceptable 17 years later not to have regulations to implement a law that now applies to a 19-to-20 billion-dollar-a-year business," said McCain, R-Ariz., who chairs the Senate Indian Affairs Committee.

McCain said he will send a stern letter to Interior Secretary Gale Norton asking when Congress can expect to have regulations, which would help tribes, communities and the government know what to expect when an off-reservation casino is proposed.

"I don't see how we can effectively regulate Indian gaming and certainly exercise congressional oversight unless there are regulations to implement the laws we pass," McCain told George Skibine, the Interior department official in charge of policy and economic development for Indian Affairs.

McCain has argued that Congress never intended Indian gambling to grow into Las Vegas-style operations bringing in almost $20 billion a year, nearly double the take from Nevada's gambling industry. He is holding a series of hearings to decide how to strengthen the Indian gaming act by making Indian gaming more transparent and increasing the safeguards to protect patrons.

Skibine said the department has tried to write regulations in the past, but the process hit a snag as the administration changed hands.

Meanwhile, tribes have applied to open casinos near cities such as Oakland, Calif., and Denver, causing conflicts between residents and Indian tribes.

On Wednesday, residents who have fought Indian casinos pleaded for the right to participate from the beginning as the government considers a tribe's application to open an off-reservation casino. Tribal leaders reminded senators that Indians are following the law and seeking compensation for lands that were taken away from them more than a century ago.