WASHINGTON — Pepco and Exelon, the two companies whose proposed merger was denied by the D.C. Public Services Commission last week, say that the regulators dropped the ball.

The two companies released a joint statement on Monday that claimed that denial of the merger deprives customers in Pepco’s service area — D.C., Maryland, Delaware and New Jersey — of “hundreds of millions of dollars in direct financial benefits, improved reliability and storm response, renewable energy projects, and commitments that will preserve their local utility’s role as a strong community partner and contributor to economic growth.”

D.C. is the only one of the four service areas to turn down the merger.

“We believe our merger proposal is in the public interest, and we will continue working to complete the merger, which all other jurisdictions have approved,” the joint statement says.

While Maryland approved the merger, it attached 46 conditions.

The commission said when denying the merger that it found no evidence that ratepayers would, in fact, benefit from the merger, and that all the benefits would go to Exelon.

“Pepco will become a second-tier company in a much larger corporation whose primary interest is not in distribution, but generation,” Commission Chairwoman Betty Ann Kane said at the time.