Earlier this year, T-Mobile and Sprint announced that they would merge. If approved, their combination would shrink the number of major wireless carriers in the United States from four to three. Now, 14 different organizations have penned a letter to Democratic House leaders requesting a hearing on the proposed merger.

The letter, which is signed by leaders of groups like the Open Markets Institute and Public Knowledge, was addressed to two of the most influential Democratic House lawmakers, Reps. Jerry Nadler (D-NY) and Frank Pallone (D-NJ). Once the new Congress kicks off in January, both lawmakers will be chairing committees with oversight jurisdiction on the potential merger deals.

“Announcing hearings to examine the single largest pending wireless telecommunications merger, and one of the largest in the nation’s history, would be an excellent first step to implementing your vision for stronger antitrust enforcement, protecting consumers, promoting competition, and standing up for American workers,” the groups wrote.

The Senate Judiciary Committee held a hearing in June with both T-Mobile’s CEO John Legere and Sprint’s executive chairman Marcelo Claure, but there have been no similar hearings in the House.

Both Nadler and Pallone have made comments in the past criticizing the proposed deal between the two telecoms. In April, shortly after the merger was announced, Pallone penned a letter to the current Republican chair requesting a hearing to discuss the state of media mergers in the US.

“We have not had a single hearing to examine the state of competition as the industry makes this change or how a loss of a competitor could affect consumers or workers,” Reps. Pallone and Doyle said. “The public deserves to understand whether further consolidation will speed up or slowdown that deployment and what the change will do for American workers.”

Nadler, who will likely lead the House Judiciary Committee next year, has criticized the state of antitrust enforcement in the US as well. In May, he said that the “decline of antitrust enforcement over the past several decades has been an economic catastrophe for millions of workers who have lost their jobs or have seen their wages lowered.”

Earlier this month, the Federal Communications Commission opened up a commenting period on the proposed merger, asking for feedback from the public. The Commission paused the normal 180-day review clock, an informal approval deadline, back in September. That won’t start again until after the commenting period ends in December.