NEW YORK  — NBA players delivered a resounding but risky response to one more ultimatum from NBA Commissioner David Stern: See you in court.

The players’ association rejected the league’s latest proposal for a new labor deal Monday and began disbanding, paving the way for a lawsuit that throws the season in jeopardy.

Negotiating went nowhere, so now the union is going away.

And Stern said “nuclear winter” is coming.

“We’re prepared to file this antitrust action against the NBA,” union executive director Billy Hunter said. “That’s the best situation where players can get their due process.”

And that’s a tragedy as far as Stern is concerned.

“It looks like the 2011-12 season is really in jeopardy,” Stern said in an interview aired on ESPN. “It’s just a big charade. To do it now, the union is ratcheting up I guess to see if they can scare the NBA owners or something. That’s not happening.”

Hunter said players were not prepared to agree to Stern’s ultimatum to accept the current proposal or face a worse one, saying they thought it was “extremely unfair.” And they’re aware what this battle might cost them.

“We understand the consequences of potentially missing the season; we understand the consequences that players could potentially face if things don’t go our way, but it’s a risk worth taking,” union vice president Maurice Evans said. “It’s the right move to do.”

But it’s risky.

Hunter said all players will be represented in a class-action suit against the NBA by attorneys Jeffrey Kessler and David Boies — who were on opposite sides of the NFL labor dispute, Kessler working for the players, Boies for the league.

“Mr. Kessler got his way, and we’re about to go into the nuclear winter of the NBA,” Stern told ESPN. “If I were a player … I would be wondering what it is that Billy Hunter just did.”

The league already has filed a pre-emptive lawsuit seeking to prove the lockout is legal and contends that without a union that collectively bargained them, the players’ guaranteed contracts could legally be voided.

During oral arguments on Nov. 2, the NBA asked U.S. District Judge Paul Gardephe to decide the legality of its lockout, but he was reluctant to wade into the league’s labor mess. Gardephe has yet to issue a ruling.

Two years of bargaining couldn’t produce a deal, with owners’ desires for more competitive balance clashing with players’ wishes to keep the salary cap system largely intact. The sides last met Thursday, when the league offered a revised proposal but told the players there would be no further negotiating on it.

Stern, who is a lawyer, had urged players to take the deal on the table, saying it’s the best the NBA could offer and advised that decertification is not a winning strategy.

Players ignored that warning, choosing instead to dissolve the union, giving them a chance to win several billion dollars in triple damages in an antitrust lawsuit.

“This is the best decision for the players,” union president Derek Fisher said. “I want to reiterate that point, that a lot of individual players have a lot of things personally at stake in terms of their careers and where they stand. And right now they feel it’s important — we all feel it’s important to all our players, not just the ones in this room, but our entire group — that we not only try to get a deal done for today but for the body of NBA players that will come into this league over the next decade and beyond.”

Fisher, flanked at a press conference by dozens player representatives and superstars including Kobe Bryant and Carmelo Anthony, said the decision was unanimous. But there were surely players throughout the league who would have preferred union leadership put the proposal to a vote of the full membership, with many ready to go back to work.

The sides still can negotiate during the legal process, so players didn’t want to write off the season just yet.

“I don’t want to make any assumptions,” union VP Keyon Dooling said. “I believe we’ll continue to try to get a deal done or let this process play out. I don’t know what to expect from this process.”

Hunter said the NBPA’s “notice of disclaimer” was filed with Stern’s office about an hour before the news conference announcing the move. Now, the NBPA is in the process of converting to a trade association as the fight shifts to the courts.

“The fact that the two biggest legal adversaries in the NFL players dispute over the NFL lockout both agree that the NBA lockout is now illegal and subject to triple damages speaks for itself,” Kessler said in an email to The Associated Press. “I am delighted to work together with David Boies on behalf of the NBA players.”

Hunter said the bargaining process had “completely broken down.” Players made numerous economic concessions and were willing to meet the owners’ demands of a 50-50 split of basketball-related income — a transfer of about $280 million annually from their feeling the league’s desires to improve competitive balance would hurt their guaranteed 57 percent under the old deal — but only if the owners met them on their system wishes.

“This deal could have been done. It should have been done,” Hunter said. “We’ve given and given and given, and they got to the place where they just reached for too much and the players decided to push back.”

Over the weekend, Stern said he would not cancel the season this week.

Regardless, damage already has been done, in many ways.

Financially, both sides have lost hundreds of millions because of the games missed and the countless more that will be wiped out before play resumes. Team employees are losing money, and in some cases, jobs. And both the owners and players eventually must regain the loyalty of an angered fan base that wonders how the league reached this low point after such a strong 2010-11 season.

“It’s horrible,” said Ty Agee, president of the Beale Street Merchants Association in Memphis, Tenn. “This is bad. Personally, I don’t believe they will be able to fix it. This is really, really bad.”

And it was seemingly destined. Hunter said he believed years ago owners were going to lock out the players until they could force through the changes they sought. Given that, he has been criticized for not disbanding the union sooner in hopes of creating some leverage that the union never had.

The proposal rejected by the players called for a 72-game season beginning Dec. 15.

On Sunday, the league made a very public push on the positives of the deal — hosting a 90-minute twitter chat to answer questions from players and fans, posting a YouTube video to explain the key points and sending a memo from Stern to players urging them to “study our proposal carefully, and to accept it as a fair compromise of the issues between us.”