Nearly 15,000 nurses at three of New York City’s largest hospital systems went on strike Monday morning after contract negotiations failed to produce an agreement.

The New York State Nurses Association said talks broke down with Mount Sinai Hospital, Mount Sinai Morningside, Mount Sinai West, Montefiore and NewYork-Presbyterian after months of bargaining.

“Unfortunately, we have made very little progress at the bargaining table,” NYSNA president Nancy Hagans told NY1.

Nurses at Mount Sinai hospitals began walking off the job at 6 a.m. Monday, while nurses at Montefiore and NewYork-Presbyterian began striking at 7 a.m., according to the union.

"The last strike we had a lot of things that went well for us and now Sinai wants to take those things away that we got that we fought so hard for, so for the safety of our patients we would like to maintain the current ratios that we do have," Mount Sinai Hospital nurse Wilhemina Dimonden said.

Union leaders said negotiations stalled over safe staffing levels, health care benefits and protections from workplace violence.

“Our key sticking points in negotiation continue to be safe staffing for our patients, protection from workplace violence and health care for frontline nurses,” Hagans said. “We continue to call on hospital management to come to the table and settle contracts that keep patients and nurses safe.”

The union is accusing hospital management of refusing to make meaningful progress and threatening cuts to nurses’ health benefits. NYSNA said those cuts could affect nearly 27,000 nurses statewide.

Hospitals said they are prepared to maintain patient care during the strike and plan on continuing with negotiations.

“NYSNA’s leaders continue to double down on their $3.6 billion in reckless demands, including nearly 40% wage increases,” said Joe Solmonese, Montefiore’s senior vice president for strategic communications. “We remain resolute in our commitment to providing safe and seamless care, regardless of how long the strike may last.”

"We're ready to keep negotiating a fair and reasonable contract that reflects our respect for our nurses and the critical role they play, and also recognizes the challenging realities of today's healthcare environment," a spokesperson for NewYork-Presbyterian said in a statement.

"Unfortunately, NYSNA decided to move forward with its strike while refusing to move on from its extreme economic demands. We are ready with 1,400 qualified and specialized nurses — and prepared to continue to provide safe patient care for as long as this strike lasts," a Mount Sinai spokesperson added. 

Mayor Zohran Mamdani joined nurses on the picket line at NewYork-Presbyterian/Columbia University Irving Medical Center Monday morning.

"The executives are not having difficulty making ends meet. But for too many of the 15,000 nurses who are on strike, they are not able to make their ends meet," he said. "They are not asking for a multimillion-dollar salary. What they are asking for is for their pensions to be safeguarded, to be protected in their own workplace, to receive the pay and the health benefits that they deserve."

Gov. Kathy Hochul said state officials will be on site to monitor patient care.

“While negotiations will continue, we expect strikes to begin tomorrow at three hospital systems in Manhattan and the Bronx,” Hochul said in a statement Sunday.

She said the state’s Department of Health will have staff at affected hospitals for the duration of the strike and signed a two-week executive order allowing hospitals to access additional resources.

“My top priority is protecting patients and ensuring they can access the care they need,” Hochul said.

Nurses on the picket line told NY1 that the support of people passing by, horn honking and cheers is keeping them going.

Each medical center is negotiating independently with the union, and several other private hospitals in and near the city have reached deals in recent days to avert a possible strike.