REVERE – With the option of a major health insurance savings no longer available to him, Mayor Thomas Ambrosino is weighing city cost cutting measures, including more employee layoffs.Ambrosino proposed saving the city $200,000 to $400,00 by reducing its share of retired teachers’ health insurance premiums from 90 percent. For 367 retirees, an increase in their premium share from 10 percent to 15 percent, or even 25 percent, represents a doubling, even tripling, of their health costs.Before City Council members summarily rejected his retiree proposal on Monday, Ambrosino summed it up by calling it “painful but not unfair.””Given the massive deficits we’re facing, we can’t afford to treat retired teachers differently.”Ambrosino on Tuesday said he is “uncertain at this point” about additional cuts needed to make up the city’s revenue shortfalls.The problem facing Ambrosino and most municipal leaders across the state is reductions in state aid spanning this year and 2010. Revere, like most communities, relies on a mix of local property tax dollars and state tax dollars to pay for the cost of government.With $1 million cut from the city’s current state aid allocation and up to $3.7 million next year, Ambrosino is scrambling to find savings to match the reductions.To cover the gap, 13 city workers have been laid off, 45 employees have had their hours cut and City Hall hours have been reduced. Ambrosino has also proposed increased parking fines, cutting overtime for city workers and tapping city reserve funds to cover the shortfall.”We will have to look for other ways to make up significant gaps in funding,” he said Tuesday.Councilors like Charles Patch said the city can save money by reducing city vehicle costs and other expenses. He said retired teachers were the wrong target for Ambrosino to pick for cost savings and noted the average retiree receives a $17,000 a year pension.”How can these people take in a 200 percent increase in insurance?” he asked.Former educator and School Committee member Carol Tye said unionized teachers saved the city $500,000 in the 1980s by agreeing to shift retirees’ insurance from the city retirement system to the state-run Group Insurance Commission. “So many (teachers) did not get a lot of money teaching but there was a covenant: ‘We’ll look after you when you retire,'” Tye said.