L.A. Mayor Antonio Villaraigosa on Monday announced a deal between the city and the Bonaventure Hotel that removes a major obstacle to the development of a $400 million, 1,100-room convention center hotel.

The deal, which took shape after a week of negotiations between Villaraigosa, Bonaventure owner Peter Zen, Councilwoman Jan Perry and Maria Elena Durazo, president of Hotel and Restaurant Employees Local 11, allows Zen to convert about 30 percent of his hotel’s 1,350 rooms into condominiums.

In return, Zen agreed to drop his lawsuit and a threatened ballot referendum blocking the construction of a convention center hotel. Zen also agreed to give all workers at the Bonaventure three years of job protection from the time the rooms are taken out of use for condominium conversion.

Zen said the negotiations were initiated by the mayor’s office on Oct. 10. The framework for the agreement was reached last Thursday, and a press conference was initially scheduled for Friday morning. But Zen said his lawyers needed more time to review the agreement.

Zen said the agreement removes the potentially thorny obstacle of union opposition to conversion of the Bonaventure’s rooms to condos. “That’s the biggest gain for us,” he said. He said there is no firm timetable for the conversion project. “We might convert the rooms right away or we might not,” he said.

The City Council last month approved an agreement with the proposed convention center hotel developers led by Apollo Advisors, Wolff Urban Management and assisted by Anschutz Entertainment Group to forgive up to $289 million in hotel bed taxes for 25 years. Zen had been the leading voice opposing the incentives, saying they subsidized a competitor that would take business away from his hotel.

The convention center hotel is to serve as an anchor for a $1 billion entertainment complex next to the Staples Center called L.A. Live that will include a 7,000-seat theater, ESPN cable television studios, restaurants and shops.