RIALTO - Work to close the city's airport to make way for an ambitious development project could be months away, unless the City Council wants to rethink the plan.

In recent weeks, city officials have completed negotiations with a number of government agencies so the city can turn the Rialto Municipal Airport into the Renaissance Rialto development project.

The next step is to complete the plans and send them to the City Council - something that probably won't happen until the fall or end of the year.

But now there are murmurs that the plans need an extra spark.

"I'm convinced that the smart thing to do is to make Rialto a destination spot," said City Councilman Ed Scott. He mentioned the California Speedway in Fontana and the new stadium in Ontario as examples of regional draws.

The airport sits in the heart of what city officials and a development partnership between the Upland-based Lewis Group and Ross Perot Jr.'s Hillwood want to turn into Renaissance Rialto.

The latest plans for the project include shopping, about 2,000 homes, a school, parks and industrial and office space. A SuperTarget would anchor the retail center.

"We're going to need at some point to be very clear on what we're trying to accomplish," said City Councilwoman Deborah Robertson.

She said she is a fan of transit-oriented development and might want to bring an educational institution specializing in local concerns like

transportation and logistics, environmental issues or language to the city.

"I think we all are looking for the ideal draw," she said.

A regional draw could be a good idea as long as it complements other landmarks, like the Speedway, said City Councilwoman Winnie Hanson.

"I'm interested. I think it's a great thing to explore," she said.

Hanson said she doubted altering the project would delay it.

Approving the plan is important so the developers can start purchasing the airport property from Rialto and fronting money to relocate the tenants. Many tenants also won't sign on to fill the shopping area until a project has been passed.

The airport probably won't be closed for two more years because new facilities have to be built for the tenants before they can leave Rialto. Money to do that will initially come from the developers once a project is approved.

In the past few weeks, the city and the Federal Aviation Administration formally agreed on the value of the airport land and Caltrans officials agreed to give Rialto access to property the city needs to build Renaissance.

Federal legislation passed in 2005 allowed the city to close the airport with the condition that it had to pay 45percent of the value of the airport property to San Bernardino International Airport, which will receive many of Rialto's tenants.

Rialto has also submitted an airport closure plan to the FAA.

"I don't think we have any issues with this plan," said FAA spokesman Ian Gregor.