Mayor Martin J. Walsh threatened Tuesday to veto a proposed $25,000 pay increase for Boston city councilors, saying on the eve of an expected vote that the raise is too large.
The mayor said he is open to reviewing the council’s final proposal, but will not sign off on boosting council salaries from $87,500 to $112,500.
“In its current form, I don’t find this proposal acceptable, and I won’t support it,’’ Walsh said in a statement.
Council President Bill Linehan, who proposed the raise last month, could not be reached Tuesday to respond to the mayor’s veto threat. Last month, Linehan proposed a 29 percent increase for himself and his colleagues, saying the council had not received a raise in eight years.
Walsh must sign off on any pay raise. But two-thirds of the council could vote to override the mayor’s veto.
Walsh came into office in January and pledged a new era of cooperation with the council, which had been dominated by Mayor Thomas M. Menino . A showdown over the proposed raise could fray the relationship between the new mayor and the council.
The council is expected to take up the pay raise at Wednesday’s weekly meeting, and councilors will have the opportunity to amend the proposal. Although it appears that a majority of the 13 councilors supports the raise, a handful objects to its size.
Linehan initially pressed for a raise this year, but the State Ethics Commission raised concerns. Councilors are prohibited from participating in matters involving their financial interest, including a pay raise, according to the state ethics law.
Linehan then agreed to delay the raise until after January 2016, after the next City Council election.
Councilors received their last raise in 2006, which extended to the next year, increasing their pay to $87,500, from $75,000. Linehan and other councilors have maintained that the proposal would give them the same salary adjustments as given to the majority of unionized city workers.
But city data released Tuesday shows a 29 percent raise would increase councilors’ salries more than than those of other municipal employees.
City workers received raises amounting to an average of 2.7 percent a year under contracts that stretched from July 2007 to June 30, 2016. The measure proposed by Linehan would amount to a 3.2 percent annual increase for councilors over the same period, the city data show.
The proposed increase would be slightly higher than was given to firefighters, whose contract called for an average annual pay increase of 3.1 percent, according to city figures. The contract for patrol officers called for a 2.8 percent annual pay increase.
In addition, the council’s proposed increase would top the 2.4 percent average annual pay increase for other union members in city government.
In addition to Linehan, several councilors, including Councilor Frank Baker of Dorchester, indicated they would support the pay increase.
“I’ll support it no matter what,’’ Baker had declared previously.
But other councilors — including Matt O’Malley, Ayanna Pressley, and Josh Zakim — said they would not back a raise to $112,500.
Pressley had argued the council should use the 2013 recommendation of the city’s Compensation Advisory Board as a guide for pay raises.
The compensation board in 2013 had urged an 8.6 percent pay increase for the mayor, thus bumping his salary to $190,000.
The board did not recommend a pay increase for the councilors. Traditionally, councilors receive half of what the mayor makes.
City officials did not act on the board’s recommendation.