CHICAGO >> The Chicago Cubs and owners of rooftop venues across the street from Wrigley Field appeared to be headed toward the legal equivalent of bench-clearing brawl, after the team announced Thursday it will now push to erect more signs in the outfield than the city has approved.

Owners of the 15 rooftop venues immediately vowed to fight in court what they see as a threat to their views and livelihoods.

“We’ve spent endless hours in negotiations with rooftop businesses,” Cubs chairman Tom Ricketts says in a video posted on the team’s website. “We’ve gotten nowhere in our talks with them to settle this dispute. It has to end.”

The rooftop owners, who have spent millions of dollars on their venues and have a contract with Cubs through 2023 requiring them to pay the team 17 percent of their gross annual revenue, were just as adamant in insisting they would vigorously defend their businesses.

“It appears their zeal to block rooftop owners, who pay them millions of dollars a year in royalties, knows no bounds,” said Ryan McLaughlin, a spokesman for the rooftop owners, whose contract with the team calls for them to share their revenues with the Cubs. “Unfortunately, this decision by the Ricketts family will now result in this matter being resolved in a court of law.”

Last summer, the City Council approved the Cubs’ $500 million renovation plan for the 100-year-old ballpark, which includes installing a Jumbotron in left field and a video scoreboard in right field. The plan, however, has been stalled by opposition from the rooftop owners.

Alderman Patrick O’Connor, Mayor Rahm Emanuel’s floor leader on the City Council who tried to facilitate a deal, said the two sides had been tantalizingly close to striking a deal that would have moved the right field video board to the top of a building across the street. But when owners of rooftops outside left field started complaining anew about the Jumbotron, the negotiations “started to fall apart,” he said.

Now the Cubs want to dramatically expand the renovation plan to what the team originally had proposed. The Cubs had backed away from that plan with the hope they could secure a promise from the rooftop owners not to sue if the team settled for the two signs.

“It became clear to us that at that point if we weren’t going to resolve the dispute over two signs, we may as well go forward with our original plan,” team spokesman Julian Green said.

The team, which already has the city’s permission to build the Jumbotron and the video scoreboard, wants to build a second video board in right field, four more LED signs in the outfield — each as big as 650 square feet — add 300 seats and erect light standards in the outfield. The team will present the plan to the city’s Landmarks Commission on June 5.

While the rooftop owners say their contract with the team puts them on solid legal ground, Green said the Cubs are confident as well.

“Where the contract is clear is that any expansion of Wrigley Field approved by the city of Chicago is legal,” he said.

The Cubs have maintained that it needs the added revenue from the signs to pump money back into the team so it can end its 106-year World Series championship drought — and have not-so-subtly suggested the rooftop owners are standing in the way.

“I know this plan is in the best interest of our fans and our players,” Ricketts said.

An emailed statement from Emanuel’s office was supportive.

“Like all Cub fans, the mayor doesn’t want to wait for next year and if this proposal helps the Cubs get closer to a ballpark renovation this fall — and the jobs and neighborhood investments that come with it — it’s worth taking a look at,” it said.