Consumer and media reform advocates are calling on federal regulators to reject a merger between Comcast and NBC, saying it would “seriously harm the public interest.”

“The correct response to this merger is to just say no,” said Corie Wright of the Free Press in a release.

“The pundits who are predicting this merger will be a cakewalk haven’t done a careful analysis,” said Mark Cooper of Consumer Federation of America. “This merger’s potential to foreclose competition and stifle innovation is significant and real.”

The two groups released a report (pdf) detailing how the merger would stifle traditional and online video markets, leading to higher prices for consumers.

The merger would also encourage further media consolidation, as “remaining players in both the distribution and content markets seek to muscle-up to match this new behemoth,” according to the report. That would mean less consumer choice and higher prices.