Illinois’ governor and attorney general said they are wary of a potential merger involving Chicago-based Exelon. The proposal would create the largest energy company in the country.

Exelon owns Commonwealth Edison, and is in the midst of merging with its rival Constellation energy. This week shareholders of both Exelon and Constellation approved the merger.

The companies will try to win approval from state and federal regulators as the next step in the process.

Gov. Pat Quinn said he’s not excited about the latest Exelon merger.

“You know Exelon seems to always want to be in a merger game, and I don’t know how it helps their loyal customers, families and businesses right here in Illinois,” Quinn said in a news conference Tuesday.

Attorney General Lisa Madigan said the merger would in fact hurt Illinois consumers. On Tuesday her office filed documents alleging Exelon has already used its market power to unfairly increase energy prices in Northern Illinois.

The Attorney General is calling for a hearing with the Federal Energy Regulatory Committee.