The ongoing labor dispute at Starbucks intensified as the strike expanded to over 300 U.S. stores on Tuesday, with more than 5,000 workers expected to participate in the five-day work stoppage set to conclude on Christmas Eve.

Starbucks Workers United, the union representing employees at 525 stores nationwide, announced that over 60 locations across major cities, including New York, Los Angeles, Boston, and Seattle, were closed on Monday due to the strike.

Despite the closures, Starbucks assured customers that the "vast majority" of its over 10,000 company-operated stores across the country remain operational, emphasizing a "very limited impact" on its overall business.

In a statement, the Seattle-based coffee chain reiterated its willingness to resume negotiations with the union, stating, "We are ready to continue negotiations when the union comes back to the bargaining table." The company also claimed that union delegates had previously ended bargaining sessions prematurely.

The strike comes after Starbucks Workers United rejected an earlier company offer that included no immediate wage increases and a guaranteed 1.5% pay hike in future years. The union criticized the proposal, stating that Starbucks has yet to present workers with "a serious economic proposal."

As the strike unfolds during the busy holiday season, it underscores growing tensions between Starbucks and its employees over wages and working conditions.