(Reuters) - Six U.S. senators on Tuesday asked the Federal Communications Commission and Justice Department to reject the proposed $45 billion merger of the country’s largest cable providers, Comcast Corp and Time Warner Cable Inc .

The call came from Democratic Senators Al Franken, Edward Markey, Ron Wyden, Elizabeth Warren and Richard Blumenthal, alongside Independent Senator Bernie Sanders, in letters to FCC Chairman Tom Wheeler and U.S. Attorney General Eric Holder.

“Should the transaction survive the FCC’s and DOJ’s reviews, we believe that Comcast-TWC’s unmatched power in the telecommunications industry would lead to higher prices, fewer choices, and poorer quality services for Americans,” they wrote in a rare direct call for a rejection by multiple lawmakers.

The company on Tuesday pushed back against the senators’ concerns. Spokeswoman Sena Fitzmaurice in a statement said the benefits of the deal were “demonstrated and real,” saying they included faster Internet speeds and better video services for more consumers and better connectivity for low-income Americans.

“These benefits all come with no reduction in competition for consumers,” Fitzmaurice said, citing the combined company’s expected reach of less than 30 percent of the video market and about 35 percent of broadband subscribers.

Comcast officials are scheduled to discuss the proposed merger with the Department of Justice reviewers on Wednesday in the company’s latest meeting with regulators who must approve the deal.

Bloomberg News reported on Friday that staff attorneys at the department’s antitrust division were nearing a recommendation to the chief reviewer to block the merger because of concern about its impact on consumers.