Senior board members want Frank Nero to depart as chief executive of Miami-Dade’s Beacon Council, several sources said Monday, setting up a potentially expensive exit less than a year after the tax-funded organization voted to extend his $400,000-a-year contract.

After months of strained encounters with county commissioners and Mayor Carlos Gimenez’s administration, top board members have concluded the economic-development group requires a new CEO and now are trying to reach a severance deal with Nero, according to three current board members who did not want to be named given the sensitivity of the issue.

Nero, who took the top job at the Beacon Council in 1996, declined to comment. Though he has tangled with elected leaders in the past, recent months saw the biggest threat ever to the Beacon Council’s yearly stream of public dollars as commissioners questioned whether the money was well spent. Nero and his seven top aides collect more than $1.5 million in salary, according to tax records, and the Beacon Council relies on county business taxes for about $4 million of its nearly $6 million annual budget.

The group’s top critic on the County Commission, Lynda Bell, issued a statement Monday calling for new leadership at the Beacon Council and blasting its current chief.

“If the Beacon Council, wants to more directly and cogently serve the interests of the residents of Miami-Dade County, it should start by changing its leadership structure. Otherwise public support will continue to erode,” Bell wrote. “Mr. Nero’s salary is excessive and unjustifiable.”

The Beacon Council’s main job is to lure companies to Miami-Dade, largely with county and state incentives it helps broker between the funding agencies and the businesses. But it also takes a broader role in promoting Miami-Dade’s economy and business leaders, from an upcoming awards luncheon on a cruise ship to funding a year-long look at growth industries known as the “One Community One Goal” plan.

If the board forces out Nero, it would mean a swift about-face for a group that approved a three-year extension of his contract during the summer of 2012.

The contract has not been released, and it is not known what sort of termination penalty the Beacon Council would need to pay if it fired Nero. One board member said Monday that there have been “discussions about early termination” with Nero but that no agreement has been reached. Joseph Pallot, the corporate lawyer who serves as the volunteer chairman of the Beacon Council this year, declined to comment.

Alan Becker, the Fort Lauderdale lawyer who was Beacon Council chairman when Nero negotiated his contract renewal, defended the extension, saying Nero leads “probably the most admired and the most successful development organization in the state and probably the nation.”

“Frank Nero made it that and deserved the renewal of his contract,” Becker wrote in an email, saying no board member voted against the extension. “If Frank and the Beacon Council are judged by results and not by special interests or political agendas, there would not now be the slightest question about his continued service.”

The push to remove Nero comes a week before the group’s annual awards luncheon, which is being held March 14 aboard a cruise ship at Port Miami. The Beacon Council’s executive committee meets this Friday.

A Nero departure would bring to a close an increasingly stormy tenure for the veteran economic-development chief, who has had public spats with senior board members and elected officials.

The tensions rose when Gimenez was elected mayor in 2011 and said he wanted to rethink Miami-Dade’s economic-development strategy. That same year, Gimenez and Nero ended up on opposite sides of the debate on Genting Group’s plan to build a massive casino in downtown Miami, with Nero a leading voice against the push and Gimenez citing casinos as job creators.

In October, the Beacon Council was forced into political damage control when Commissioner Bell proposed a new contract for the group and recounted a meeting she had with Nero and Pallot where she was “treated very rudely and disrespectfully.” In January, Commissioner Sally Heyman sponsored a resolution that passed unanimously calling for the Beacon Council to divert $1 million of its public dollars to grants for existing small businesses.

Heyman gave the Beacon Council until the end of March to respond to the proposed shift, and the group has been urging its members to write commissioners in support of the current funding levels.

Miami Herald staff writer Patricia Mazzei contributed to this report.