Ten days after a fellow City Council member said he intended to introduce a bill that would extend city elected officials’ maximum time in office to three terms from two, Councilman David I. Weprin announced rival legislation on Sunday establishing that only a referendum should change the city’s term limits law.

The competing bills reveal the mounting tensions at play in the Council, which is gearing up for what could be a contentious and costly political battle to modify a law that was twice approved by voters, in 1993 and 1996.

While a majority of council members are open to altering the term limits law — a telephone survey conducted by The New York Times last month found that 27 of the Council’s 51 members welcomed the idea — many are facing intense pressure from voters, who say that they, not the lawmakers, should be the ones deciding if any changes ought to be made.

“When you talk to council members privately, they’re very clear about concerns that their constituents have on this issue,” said Councilman Bill de Blasio, a Democrat from Brooklyn, who joined Mr. Weprin and Councilman Eric N. Gioia, both Democrats of Queens, for the announcement on the steps of City Hall.

The debate over whether to expand term limits heated up three weeks ago, when Mayor Michael R. Bloomberg said that he would consider a bill to extend the time lawmakers can stay in office, after repeating for months that he would respect the will of voters.

The legislation proposed by Councilman Weprin and the one put forward by his colleague, G. Oliver Koppell, on Sept. 4, which would extend term limits, are being reviewed by the Council’s legal division, which has 60 days to respond. As it stands, the term limits law will force the mayor, the comptroller, the public advocate and two-thirds of the Council — including Mr. de Blasio, Mr. Weprin, Mr. Gioia and Mr. Koppell — out of office at the end of 2009.

In an interview on Sunday, Mr. Koppell, a Democrat from the Bronx, described Mr. Weprin’s bill as “a largely cosmetic attempt at publicity” and said that he found it “highly unlikely” that the bill would receive support from a majority of the Council because its members “would not want to foreclose an option that we have.”

Mr. Weprin, who is running for comptroller, said that his bill safeguarded the public’s trust “in the people they elected to represent them in public office,” adding, “The voters have made their statement via the ballot box, and any change should continue to come via the ballot box.”

His bill has the support of several good-government groups including Citizens Union and Common Cause New York, and New Yorkers for Term Limits, a group financed by the billionaire cosmetics heir Ronald S. Lauder that in 1993 ran the original campaign to create the term limits.

“It’s all about respect for the will of the people, and that’s what this legislation does,” Ken Moltner, a spokesman for New Yorkers for Term Limits, said during the announcement.

A poll in July by Quinnipiac University found that 56 percent of voters were opposed to extending term limits to allow Mayor Bloomberg to run for re-election, even though he was their top mayoral pick.

The City Council speaker, Christine C. Quinn, who has been regarded as a mayoral candidate, said in December that she would not support any plans to alter term limits. But she has made no public pronouncements of late, which has served only to fuel speculation that she and Mr. Bloomberg might be planning to upend the law.

When asked about Mr. Weprin’s bill on Sunday, Ms. Quinn’s spokesman, Jamie McShane, said that the speaker did not generally comment on bills before they were drafted or introduced.

Source: NY Times