Workers at several Amazon warehouses across the country went on strike early Thursday morning. This was part of an effort by the Teamsters union to pressure the e-commerce giant to recognize burgeoning unions at its facilities.

The walkout comes in the final stretch of the holiday shopping rush, as customers rely on Amazon to deliver last-minute gifts. The company released a statement claiming that the strike would not affect its ability to deliver packages on time.

The International Brotherhood of Teamsters announced the strike would affect seven warehouses, including three in Southern California – in Victorville, Industry and Palmdale – and one in San Francisco. It was unclear how many workers took to the picket lines.

“What we are doing is historic,” said Leah Pensler, a warehouse worker at the San Francisco plant, according to a Teamsters news release. “We are fighting a vicious anti-union campaign and we will win.”

Frustrations over pay and working conditions have led to sporadic organizing efforts among workers at Amazon warehouses in recent years, and efforts have gained momentum across the company’s vast network of delivery drivers.

The Teamsters announced a nationwide campaign to unionize Amazon warehouse and delivery workers in the summer of 2021. The action was aimed not only at expanding its ranks, but also at protecting the wages and workplace standards of its members who work at UPS and other companies that face competitive pressure to copy Amazon’s methods.

In total, about 10,000 Amazon employees and contract workers at various Amazon facilities have pledged to join the union, a small portion of the 800,000 workers employed in U.S. warehouses, according to the Teamsters. But the Teamsters have not held formal union elections, and proposed bargaining units at those plants have not been recognized by the National Labor Relations Board, which has the authority to order Amazon to come to the bargaining table.

Amazon spokeswoman Kelly Nantel accused the Teamsters of misrepresenting their union as the official representative of many Amazon employees and contractors because they had not yet completed the process for recognition by the National Labor Relations Board.

“For more than a year, the Teamsters have intentionally misled the public by claiming that they represent ‘thousands of Amazon employees and drivers.'” They do not, and this is another attempt to spread a false narrative “ Nantel said in an emailed statement. “What you see here are almost entirely outsiders – not Amazon employees or partners – and suggesting otherwise is just another lie from the Teamsters.”

At the beginning of December, the union set a deadline for Amazon to come to the negotiating table. The union said Amazon’s refusal to meet its demand to negotiate a collective agreement set the strike in motion.

The strike, involving workers at warehouses in New York, Atlanta and other cities, is the largest industrial action against Amazon to date, the union said.

“If your package is delayed during the holidays, you can blame Amazon’s insatiable greed. We have given Amazon a clear deadline to come to the table and do the right thing for our members. They ignored it,” Teamsters President Sean M. O’Brien said, according to the news release.

Patricia Campos-Medina, executive director of the Worker Institute at Cornell University, said the strikes were an opportunity for the Teamsters to demonstrate strong support for unionization in warehouses and attract more workers.

Because Amazon is a large employer with a huge network, she said, potential disruptions are limited. Still, she said, “It’s a time when Amazon wants to shine and doesn’t want any distractions.” It’s a moment of great leverage for workers.

The e-commerce giant has waged a long, largely successful battle to stop unionization efforts in its operations and has been repeatedly accused of using anti-union tactics that violate federal law – allegations the company denies.

The Federal Labor Department has ordered a union election by workers at an Alabama warehouse to be rerun several times amid allegations of interference by Amazon.

In 2022, Amazon Labor Union, an independent union group, won a crucial union election at the JFK8 factory on Staten Island, New York – the first successful union drive at one of the company’s U.S. warehouses. However, the union struggled to secure further victories, losing an election in the neighboring facility and another in Albany shortly thereafter.

Amazon Labor Union helped Amazon workers at a fulfillment center in Moreno Valley, California, launch a union drive at the facility in 2022, but the effort stalled soon after as the group withdrew its election petition filed with the National Labor Relations Board.

After internal division hampered the organization, the Amazon Labor Union agreed to work with the Teamsters, which provided a more stable financial base and resources.

The labor push got a boost this year from the NLRB, which has questioned Amazon’s model of relying on a network of independent companies to employ tens of thousands of delivery drivers. An initial ruling this summer by an NLRB regional director in Los Angeles found that Amazon was a “joint employer” of drivers who delivered packages from the company’s Palmdale warehouse. Following that decision, the NLRB’s Atlanta office ruled that Amazon should be held liable for alleged threats and other unlawful statements directed at drivers seeking to unionize in the city.