The International Brotherhood of Teamsters announced their support of an Amazon worker strike that started Thursday after the company didn’t meet the union’s deadline for bargaining negotiations with protesters.

Amazon.com Inc. workers at the company’s sole unionized warehouse in the US joined a broader strike by the International Brotherhood of Teamsters.

Teamsters union says Amazon workers at seven warehouses plan to walk off the job Thursday morning in multiple states.

Delays may impact the arrival of packages ahead of Christmas, but wide-scale delays to deliveries appear unlikely.

A spokesperson for Amazon said the union claims they represent “thousands of Amazon employees and drivers” when they don’t.

The Staten Island Amazon facility, known as JFK8, employs more than 5,000 workers, and about 100 of them joined the picket line early Saturday.

With Christmas two days away, workers at four Amazon warehouses in Southern California are on strike Monday on claims the corporate giant refuses to recognize their union and negotiate fair contracts.

Amazon delivery drivers and Starbucks baristas are on strike in a handful of U.S. cities as they seek to exert pressure on the two major companies to recognize them as unionized employees or to meet demands for an inaugural labor contract.