The Department of Justice on Thursday filed a civil antitrust lawsuit to block the pending merger of Harris Corp. [HRS] and L3 Technologies [LLL], but said if Harris divests its night vision business the deal can go through as long as the civil court agrees.

Harris already has agreed to sell its night vision business, announcing a $350 million deal in early April with Elbit Systems of American for its business that sells night vision goggles and other night vision systems. That deal is still pending regulatory approvals. Elbit Systems of America is a U.S.-based division of Israel’s Elbit Systems [ESLT].

Harris and L3 have maintained that their merger is on track for a mid-2019 close.

The Justice Department complaint says that “Harris and L3 are the only suppliers of U.S. military-grade image intensifier tubes for night vision devices such as goggles and weapon sights that are purchased by the DoD.” Without competition for the image intensifier tubes, the DoD would likely face higher prices and less industry effort to spend on research and development.