The move follows a U.S. request in January for Mexico to review whether workers at the call centers in central Hidalgo state were being denied their association and collective bargaining rights.
At the time, U.S. officials said they had found evidence of "egregious" labor rights violations at the call centers.
Atento operates Hidalgo call centers offering customer service to BBVA bank customers.
Late last month, Mexican authorities concluded an investigation acknowledging the company may have violated labor rights but that remedial actions had already been taken.
On Tuesday, the U.S. trade office said it had not been able to cooperate successfully as in previous cases, instead opting to request the panel to verify Atento's compliance with Mexican labor laws.
"Pursuing a panel in this case indicates the seriousness of the issues involved," according to the trade office statement, which quoted International Labor Affairs Deputy Undersecretary Thea Lee.
The statement went on to note that the United States remains open to collaborating with Mexico to find a resolution.
(Reporting by Raul Cortes; Writing by Sarah Morland; Editing by David Alire Garcia)
