A $7.01 billion budget calling for layoffs and furloughs of thousands of workers, but characterized as a work in progress, was signed into law Tuesday by Los Angeles Mayor Antonio Villaraigosa.

"Our work on this budget is far from complete," Villaraigosa wrote to the City Council. "The nature of the economic crisis will require us to calibrate and adjust the budget to constantly evolving realities. The duration and depth of the recession, the impact of the state budget crisis on the city and the outcome of negotiations with our labor partners remain uncertain."

With no vetoes, the spending plan does not need to return to the City Council for final approval and will take effect on July 1. However, with all the financial uncertainties in the local economy, more review of the budget is expected in coming weeks.

The budget calls for spending cuts by individual departments of anywhere from 10 to 30 percent, while protecting the Los Angeles Police Department with funding to hire more than 400 officers to replace those expected to leave this year.

Villaraigosa said the decision by the City Council to reject his public-private partnership plan on the sale of parking garages means an additional $96 million in savings will need to be found. He has asked each city department head to report to his office on their plans to live within those limits, with cuts of $41 million to civilian departments and $54 million to police and fire. At the same time, he said he was prepared to use the city's reserve fund to maintain public safety. Villaraigosa also warned that furloughs and layoffs might have to be increased to meet a balanced budget.

There is no firm figure on layoffs - there have been estimates that it could reach 3,000 workers. "We won't know that figure until we have a better idea on revenue," Chief Legislative Analyst Gerry Miller said.

Councilman Bernard Parks, chair of the council's Budget and Finance Committee, said the spending plan will have to be revised throughout the year - and even before it takes effect on July 1.

Parks has scheduled a meeting for Monday to discuss the impact of the May 19 election in which voters turned down various proposals dealing with state funding that has increased the amount expected to be taken from local government to $60 million to $120 million. Also, he said he is again prepared to look at further cuts for the LAPD.

"We are expecting to see layoffs and furloughs among civilians, but without some sacrifice by police and fire, the city work force could be devastated," Parks said. "Seventy to 80 percent of our budget goes for public safety and that does not leave a lot for parks and libraries and street repair. And it's the civilians who run the city.

"Police and fire respond to emergencies, but it's the civilians who open the rec centers. It's the civilians who repair pipes and roads. It's the civilians who clean up afterwards." Also, he said the committee will be briefed on the status of negotiations with city unions on the "shared sacrifice" called for by the mayor to reduce city spending.

Villaraigosa has asked unions to forego a cost-of-living increase, agree to voluntary furloughs of one hour a week and accept a 2 percent increase in payments for pensions. "That's a $320 million share of the budget," Parks said. "If we don't get that, it will just mean more layoffs and cuts."

Parks said he can foresee the city adopting a plan similar to the state where some agencies are closed one or two days a month. "We may have no other choice," Parks said. "Just from a payroll point of view, it's something we have to look at." Parks estimated the city saves $4 million in payroll every day it is closed.