There are many fears over the proposed merger of Comcast Corp. and NBC Universal Inc. But here's a new one - the cable company could monopolize the business-news market through its ownership of CNBC.

New York media firm Bloomberg L.P. says Comcast would have the incentive to keep the currently unrated Bloomberg TV buried in its cable TV channel lineup, permanently sealing CNBC's position as the No. 1 business-news channel.

Seeking to avoid this fate, Bloomberg wants help from the federal government. It is asking regulators to consider forcing Comcast to sell the highly profitable CNBC as a condition of the proposed $30 billion deal for NBC Universal.

Or, if regulators are unwilling to go that far, they could tell Comcast that it has to "neighborhood" business-news channels on its cable system - which is another name for giving Bloomberg TV prime real estate on the cable dial next to CNBC. (CNBC is on Channel 47 and Bloomberg TV on Channel 103 on Comcast in Center City.)

Comcast says it has tried to settle its dispute with Bloomberg TV, but it could not reach an agreement. It and others say the New York media company appears to be using the merger review process to renegotiate terms for its carriage deal with Comcast, which is not the purpose of the merger review.

Rather than hurting Bloomberg TV, Comcast says it has expanded its distribution of Bloomberg into an additional 1.5 million Comcast homes since the NBC Universal deal was announced last December.

"We have a current long-term deal with Bloomberg TV that we entered into when we had no competitive business channel and we were not thinking of acquiring a competitive business channel," David L. Cohen, Comcast's executive vice president, said Friday. "We've done nothing to disadvantage Bloomberg's position since the deal was announced."

Added Cohen: "All the decisions we've made to date have nothing to do with CNBC."

The Bloomberg-Comcast dispute emerged in the last several weeks and cuts to the core issue of the continuing federal regulatory review of the proposed merger: whether Comcast would gain excessive power in the pay-TV industry by combining one of the nation's largest programming companies, NBC Universal, with the largest cable TV network.

"Bloomberg's complaint is a perfect example of the overarching concerns we have with the merger," Mark Cooper, director of research at the Consumer Federation of America, said Friday. Cooper has testified against Comcast-NBCU.

"The most important thing is that they have stepped forward publicly and said it," he said.

With NBC Universal, Comcast could extend its control of "must-have" programming to news, women's programming, and Hispanic shows, Cooper said. "They add a tremendous amount of content that spans critical categories," he said.

Bloomberg has hired Kevin Martin, the former Federal Communications Commission chairman, to lobby its position at the regulatory agency he once headed.

Bloomberg has other political connections as well. New York Mayor Michael Bloomberg founded the company in 1981, although he no longer has an active role in management and is not a board member. The company is best known for its financial research and news wire.

Bloomberg spokeswoman Jocelyn Austin said Friday that the company would not comment. A Bloomberg TV official who spoke earlier on background said the company feared having its business channel placed in "outer Siberia" on the Comcast system.

Bloomberg TV is distributed by pay-TV companies to 67 million homes and will produce $130 million in revenue and earn a 35 percent profit margin in 2010, research firm SNL Kagan says.

Meanwhile, CNBC will produce an estimated $714 million in revenue this year and earn a 61.5 percent profit margin. Pay-TV operators distribute CNBC to 100 million homes.

The issues here are not new. Congress and regulators have tried to resolve concerns that cable operators would give special treatment to their programming channels for two decades.

In recent years, the independent Big Ten Network and the NFL Network claimed that Comcast broadly distributed the Comcast-owned Golf Channel and Versus channels on its cable system while proposing to place Big Ten and NFL on a little-watched, extra-cost sports tier. The two independent channels eventually reached carriage agreements with Comcast.

Joel Kelsey, a policy analyst at the Consumers' Union, said he believed that limits were necessary on Comcast in the NBCU deal.

"The merged conglomerate would be able to leverage its market power to limit the distribution of other companies' content and limit the choices consumers have in looking for that content," he said.

Cohen said Comcast had neither the economic power in the cable-distribution business nor in the national programming market with NBC Universal to do what its critics say it could. "As consumers demand these networks, we will supply them, because if we don't, our competitors will," he said.

Steve Wildman, director of the Quello Center for Telecommunication Management and Law at Michigan State University, said he did not buy Bloomberg's position.

"The standard intuition is that when someone is big they can exploit that bigness to their own advantage," Wildman said. But "overall there has not been systemic evidence that vertical integration [of cable and content companies] has led to discrimination against competing networks," he said.

Anyway, Wildman said, the government shouldn't be telling Comcast where to place Bloomberg TV in its channel lineup.

Verizon's FiOS TV or DirecTV could place Bloomberg TV and CNBC side-by-side in the channel lineup and pay-TV users could subscribe to them if they were unhappy with Comcast, he said.