Nassau County workers will have to agree to an across-the-board pay cut of 7 percent to avoid layoffs, Nassau County Executive Thomas Suozzi told a special session of the County Legislature Monday.

Nearly 1,000 workers -- including police officers -- would be laid off this year and civilian layoffs would leave some county offices open only four days a week, he said. Parks would be closed or have their hours curtailed, and the budgets of neighborhood-based social programs would be slashed, he added.

Faced with a downward spiral in sales tax revenue, Suozzi announced a combination of cuts in services and increases in revenue that would close an estimated gap of at least $130 million, and perhaps $150 million, in a $2.6 billion budget that went into effect barely a month ago.

"Things are as bad as they can be," Suozzi said as he outlined the scope of his cuts for the legislators and an audience that included leaders of the unions representing most county workers.

"I do not want to lay off workers in the middle of a recession. I do not like the idea of closing senior centers and parks, or imposing a tax on home heating oil," Suozzi said.

"But this is the reality that we face if we don't get the help we need from Nassau County's employee unions," he said.

The plan calls for:

* About $50 million in added revenue from a new Medicaid reimbursement formula now being worked out in Washington.

* Dramatic cuts in social programs, such as youth services -- which would not be necessary if the county gets state permission for about $30 million in local initiatives, such as installing cameras to catch red-light violators, and imposing a tax on cigarettes.

* Layoffs of several hundred county workers, including more than 200 police officers -- which would not be necessary if the county gets $50 million in savings from its unions through some combination of cuts in salary or benefits.

* Another $5 million in savings would come from cuts in salary or benefits for nonunion, managerial employees.

The current budget was proposed by Suozzi on Sept. 15, the day Lehman Brothers collapsed, and both the national economy and the outlook for the county's sales tax revenue has been on a prolonged slide since then.

The proposed budget had originally anticipated sales tax increasing by 2.5 percent this year, but now Suozzi said he has adopted a more pessimistic outlook, that will it drop by 6 percent.

The budget gap created by the revised sales tax figures amounts to $100 million. The county also expects to earn $10 million less from investment income and $20 million is at risk if the state does not act on request for the county to raise other revenue on its own.

Aides to Suozzi said he had deliberately structured the proposal so that the harshest cuts could be avoided if the state legislature and the unions representing county workers agreed to offsetting actions.

Draconian cuts to youth groups, day care and senior citizen centers, and other community-based groups could be avoided if the state legislators representing those areas were able to secure state permission to allow the county to set up cameras to catch red-light violators, put a surcharge on traffic tickets and give Nassau a cigarette tax like New York City's, the aides said.

Jerry Larichiutta, president of Local 830 of the CSEA, representing most civilian county workers, said any changes to the union contract would have to be approved by his members.

"Whatever happens, it will be up to our members to vote on it," he said.

The head of the main police union called the layoff proposal "irresponsible."

"We want to see a real plan, an alternative one," said Jim Carver, president of the Police Benevolent Association.