WASHINGTON (Reuters) - The 700,000-member Communications Workers of America (CWA) union said on Tuesday it would oppose a deal to merge wireless carriers Sprint S.N and T-Mobile, arguing that such a move would cost tens of thousands of jobs in the United States.

A Sprint sign is seen on top of a Sprint retail store in Manhattan, New York, U.S., September 22, 2017. REUTERS/Amr Alfiky

The companies are expected to announce an agreement in the first half of November to create a company that would have more than 130 million U.S. subscribers, just behind Verizon Communications Inc VZ.N and AT&T Inc T.N.

The deal would have to be approved by the Federal Communications Commission and the Justice Department’s Antitrust Division.

The union cited a 2016 study by Craig Moffett of MoffettNathanson Research which showed that some 20,000 people could lose their jobs if a deal went through.

“Allowing Sprint and T-Mobile to merge guarantees the loss of tens of thousands of U.S. jobs that would result from store closures and the consolidation of administrative work,” Shelton said.

“One of the FCC’s responsibilities is to ensure that mergers and other corporate actions are in the public interest. The massive job loss that this merger would cause is not in the public interest,” he said.

The CWA also estimated that T-Mobile has 10,000 people working in 17 U.S. call centers whose jobs could move overseas if a deal is approved, union spokeswoman Candice Johnson said.

The FCC may take job losses into consideration when reviewing a merger. Job losses are not considered in an antitrust review.

Sprint declined to comment while T-Mobile did not respond to a request for comment.

The two companies had contemplated a merger in early 2014 but scrapped the idea after initial meetings with high-level officials at the FCC and Justice Department, who had said it was unapproveable.

Many of the staffers who were in the Justice Department’s Antitrust Division in 2014 remain in place, and will be skeptical of the tie-up this time, sources have told Reuters.

But the final decision will be made by political appointees who have changed since President Donald Trump took office.

Japan's SoftBank Group Corp 9984.T controls Sprint while T-Mobile's majority owner is Deutsche Telekom AG DTEGn.DE.