Zohran Mamdani doesn’t want you to shop at Starbucks right now.

The New York City mayor-elect is urging people not to patronize the iconic coffee chain while baristas remain on strike.

“Starbucks workers across the country are on an Unfair Labor Practices strike, fighting for a fair contract,” Mamdani wrote on X on Thursday evening. “While workers are on strike, I won’t be buying any Starbucks, and I’m asking you to join us.”

The open-ended strike coincided with Red Cup Day, when the chain offers free reusable holiday cups to customers. Historically, it’s driven record sales for the company.

On Thursday, when the strike began, roughly 1,000 workers across 65 stores were expected to strike, according to the union. A Starbucks spokesperson at the time said that 99.9% of stores remained open.

The work stoppage could expand to more than 500 stores if negotiations do not resume, the union said in a statement. In the US, Starbucks has 16,864 stores, according to its most recent earnings report.

The strike comes amid stalled contract negotiations at the coffee giant, and also follows the company’s announcement of a restructuring that led to the closure of more than 600 stores across the US.

It’s the fourth strike that the union has organized since 2023, and it’s the third to have taken place since CEO Brian Niccol began leading the company in September 2024.

A Starbucks spokesperson told Business Insider on Thursday that despite the strike, the company was still on track to exceed sales expectations for the day across company-operated coffeehouses in North America.

Mamdani lending support to the striking baristas represents an early indication of how he may use the bully pulpit of his office as mayor of New York City. The Democratic socialist state assemblyman has long positioned himself as an ally to labor.

“Together, we can send a powerful message,” Mamdani wrote on Thursday. “No contract, no coffee.”