Senators Elizabeth Warren (D-MA), Bernie Sanders (I-VT) and Representative Joaquin Castro (D-TX) are calling for Law enforcement officials are investigating the joint venture between Disney, Fox and Warner Bros. to create a new service called Venu Sports. The streaming service will include sports networks from across the three companies’ portfolios, including ESPN, FOX and TNT. Last week, the companies announced that Venu Sports will cost $42.99 per month.

In the letter to the Ministry of Justice Antitrust chief Jonathan Kanter and the Federal Communications Commission According to Chair Jessica Rosenworcel, lawmakers said that this would give Venu “over 80% of nationally broadcast sports and over half of all national sports content, giving it a monopoly on televised sports.” This, in turn, could empower the new company to “discriminate against competitors and raise prices for consumers.”

They warn that the plan raises concerns among antitrust law and may be inconsistent with national ownership caps that prohibit a single company from owning channels that reach more than 39% of U.S. households. In practice, they write, Venu Sports’ competitors would have to compete with Disney, Fox and Warner Bros. “to gain access to over half of the major sports licensing rights, while simultaneously having to compete with those companies for the best product to broadcast or stream those programs.”

Lawmakers have been eyeing the deal for some time. Rep. Jerry Nadler (D-NY), the top Democrat on the House Judiciary Committee who supports antitrust legislation in the tech sector, said in April that he and Castro were “seeking more information to ensure this consolidation does not result in higher prices and less choice for consumers.” Streaming competitors also raised alarms about the joint venture. In May, Fubo, DISH Networks, DIRECTV and Newsmax were among the organizations that asked key congressional committees to investigate the deal. The companies warned that Venu Sports would have “the power and incentive to displace its competitors.”

The joint venture is the “continuation” of a consolidation trend in the television sector, said the MEPs, resulting from mergers and acquisitions in the industry. “The description of this deal as a ‘joint venture’ should not prevent the antitrust and telecommunications authorities from giving it the attention it deserves,” they wrote.

Representatives of the authorities and companies mentioned did not immediately respond to requests for comment.