LOS ANGELES (AP) _ Efforts to build a Christmas tent city for the homeless failed to get off the ground Monday in spite of a boost from a private Santa Claus.

Construction was scheduled to begin Monday evening after a benefactor agreed to put up money for the premium on a required insurance policy, but organizers of homeless people say they failed to get the policy.

''An insurance broker said it could take up to a week, maybe longer,'' said Ed Davis, a spokesman for the organization that was trying to get the tent city, called Justiceville, erected.

''We've got the money for the premium, but we can't get a policy,'' Davis said.

Joseph Grimmett, spokesman for the South Central Area Welfare Planning Council, said organizers would try to obtain the policy as soon as possible and proceed with plans.

State officials had said they couldn't waive insurance for the tent city unless a $2,500 insurance premium was furnished.

''We need a miracle,'' organizer Ted Hayes had said Friday.

But on Saturday, Canyon Country general contractor Geoff Kail donated the money for the insurance premium, project volunteer K.G. Stevens said.

State Police Sgt. Michael Morgan said the permit would be issued when proof of the insurance coverage was presented.

''Mr. Hayes said he expected to get the insurance Monday with the move-in time set for Tuesday,'' Morgan said.

About 20 people - some of them homeless - gathered near the site Monday and some said they would protest if the tents did not go up.

According to the plans for Justiceville, three giant tents would have been erected on state property near City Hall through Dec. 30 to shelter and feed 300 of the city's homeless, Hayes said.

Hayes had originally sought a permit to operate the tent city through Jan. 2, ''but a new owner is going to take over the property on Jan. 1 and they have to be out,'' said Grimmet.

''We are going to ask the new owner to allow tent city to stay up for 90 days.''

Gene Marquart, chief of the state's Office of Insurance and Risk Management in Sacramento, said the State Police permit to set up the encampment was contingent on obtaining the liability insurance.

''There is a heavy concentration of people for a long period of time and injuries could happen,'' Marquart said, suggesting organizers misinterpreted the insurance issue.

A week-long Christmas tent city, called Justiceville, was erected in 1984, Hayes said. Last year, a less-ambitious effort by the Justiceville organization set up tents again during the yuletide.

An estimated 33,000 people are homeless in Los Angeles County due to a lack of affordable housing, care for the mentally ill, unemployment and the influx of illegal aliens, private and government agency officials said.

The city has the highest rate of increase in homelessness, according to a survey presented Thursday to the U.S. Conference of Mayors in Washington.