Almost 40,000 Verizon workers went on strike on Wednesday in New York City following a deadlock in an agreement between the company and the workers’ union. The protest received a further boost as Democratic candidate Bernie Sanders joined the workers in a Brooklyn rally ahead of the New York primary slated for next week.

“Brothers and sisters, thank you for your courage in standing up for justice against corporate greed,” ABC quoted Sanders as saying to the workers outside a Verizon store in Brooklyn. “Today you are standing up not just for justice for Verizon workers, you are standing up for millions of Americans who don’t have a union.”

The communications company and the unions representing the Verizon workers failed to reach an agreement on some of the demands of the workers. The demands put forward by Communications Workers of America and the International Brotherhood of Electrical Worker included health care costs control, protection of well-paying jobs and the expansion of the ranks of the workers who have them.

The unions represent workers with job profiles like customer services representatives and network technicians at the Verizon Communications Inc., Reuters reported. Both unions have endorsed Sanders but Sanders claimed that his decision to support the Verizon workers was not influenced by the endorsements.

“I know you thought a lot about it and I know your families are gonna pay a price for going out on strike, but you have chosen to stand up for dignity, for justice,” Sanders added. “So on behalf of every worker in America who is facing the same kind of pressure, thank you for what you are doing. We are gonna win this thing,” he said.

The company said that it trained thousands of non-union employees in a way so that services are not disrupted. “There’s no way that these 10,000 people … can make up for 40,000 people who have decades of experience (in highly technical jobs),” Bob Master, a CWA representative said.

Sanders’ Democratic rival Hillary Clinton urged renewal of talks, saying businesses and the economy rely on these workers to work properly.