The Amazon Labor Union, the company’s first group of workers to organize at a U.S. warehouse, said Tuesday that it’s taken steps to affiliate with the International Brotherhood of Teamsters.

Formed in 2021 as a grassroots group of current and former workers, the ALU gained national attention two years ago by winning a historic union election in Staten Island, New York, at a facility known as JFK8.

The ALU originally eschewed major labor unions, establishing itself instead as an independent organization. But the group has struggled to negotiate a contract with Amazon, which sought to toss out the 2022 election results, and rifts have formed between leader Chris Smalls and ALU members. A group of former members sued the union last year, accusing it of violating the ALU’s constitution and asking a Brooklyn court to compel it to hold an election for union officers.

Aligning with the Teamsters, one of the largest labor unions in the U.S., could give the ALU additional heft to jumpstart negotiations with Amazon. The Teamsters, formed in 1903, has long sought to organize Amazon warehouse and delivery workers, and created an Amazon division in 2021 to support and fund workers at the company in their unionization efforts.

In a post on X, the Teamsters said the affiliation was unanimously approved by the union’s board on Tuesday. The affiliation agreement is tentative until members of the ALU and the Teamsters vote to ratify it, Smalls said in a text message.

The decision has already generated pushback from the ALU Democratic Reform Caucus, the group that sued the ALU last year. Arthur Schwartz, an attorney for the caucus, said it was unclear how the ALU will hold a membership vote to ratify the Teamsters affiliation when it “doesn’t possess a list of employees, much less a membership list.”

In March, ALU members voted to hold an election for new union officers. Smalls has said he doesn’t plan to run for reelection as ALU president. That election is expected to be held in July in person outside of JFK8, Schwartz said.

The Teamsters declined to comment further. An Amazon spokesperson also declined to comment.

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