The “Workers United” union, representing more than 10,000 coffee shop employees, announced the expansion of the ongoing strike by Starbucks workers to include four additional U.S. cities, including New York.

The strike, which began last Friday and is set to last for five days, has already led to the closure of several Starbucks locations in Los Angeles, Chicago, and Seattle, and is now spreading to cities like New Jersey, Philadelphia, and St. Louis.

This escalation follows failed negotiations between the company and the union, centered around disputes over wages, staffing levels, and work schedules.

As the crisis deepens, the union has confirmed that the strike may extend to hundreds of stores by Christmas Eve, threatening negative impacts on Starbucks’ sales during the busy holiday season.