A union representing more than 11,000 Starbucks baristas in the US says its members will go on a five-day strike starting Friday morning in a dispute over pay and working conditions.
Workers United says walkouts will take place in Los Angeles, Chicago and Seattle, with strike action spreading daily and reaching hundreds of stores by Christmas Eve unless a deal is reached with the coffee shop giant.
It follows the union's call for Starbucks to raise wages and staff, as well as implement better schedules for its workers.
“We are ready to continue negotiations to reach agreements. We need the union to come back to the table,” Starbucks said in response to the strike announcement.
The union says it represents workers at more than 500 stores in 45 US states.
“This is a last resort, but Starbucks has broken its promise to thousands of baristas and left us with no choice,” Fatemeh Alhajaboudi, a Starbucks barista from Texas, said in a statement sent to the BBC by the union.
Workers United has highlighted what it sees as an unfair pay disparity between its members and top Starbucks bosses, including CEO Brian Nichol.
Mr Niccol joined the company in September after his predecessor Laxman Narasimhan stepped down after less than two years.
The world's biggest coffee shop chain saw sales slow as it grappled with a backlash from price hikes and boycotts sparked by the Israel-Gaza war.