Faced with concerns from a labor union, the Senate Banking Committee is examining whether Alcatel-Lucent is violating a U.S. government security agreement that the telecommunications software and equipment company put in place last year to gain regulatory approval for its $11.8 billion combination.

The Committee on Foreign Investment in the United States, an interagency panel charged with examining the national security implications of cross-border deals, approved the takeover by France’s Alcatel SA of Lucent Technologies Inc. in November after the companies agreed to create a separate U.S. division to handle sensitive contracts with the Department of Defense and other government agencies. Following the instructions of the “mitigation agreement,” Alcatel-Lucent created the LGS Innovations Inc. division to manage those contracts.