A senior U.S. senator has urged two Union agencies to reject AT&T ’s advise $ 39 billion acquisition of T - Mobile USA .

Senator Herb Kohl , a Wisconsin Democrat and president of the Senate Judiciary Committee ’s antitrust subcommittee , on Wednesday called on the U.S. Department of Justice and the U.S. Federal Communications Commission to reject the deal between the country ’s secondly - largest and fourth - largest roving immune carrier .

“ I have reason out that this acquisition , if permitted to proceed , would belike cause substantive injury to competitor and consumer , would be contrary to antimonopoly law and not in the public interest , and therefore should be blocked by your agency , ” Kohlwrote in a letterto the DOJ and FCC .

The batch would boil down the routine of home carriers from four to three and would give AT&T and Verizon a combined food market portion of nearly 80 percentage , Kohl said , repeating frequent criticisms of the amalgamation . The deal would eliminate T - Mobile as a low - toll competitor to other carriers , he say .

The change in the mobile industriousness triggered by the acquisition would be “ highly dangerous ” to consumers , Kohl write .

T - Mobile USA said it was disappointed with Kohl ’s opposition to the deal .

“ While we have a great deal of regard for Senator Kohl , we strongly disagree with his analysis of this dealing , which will play significant benefits to American consumers , ” Tom Sugrue , T - Mobile ’s older vice president of governance affair , said in a statement . “ We are convinced that the reappraisal appendage will demonstrate that the merger is fully coherent with the antitrust police force and significantly advances the public interest . ”

AT&T and T - Mobile have state the deal will admit AT&T to turn over out mobile broadband service to a big geographical arena . T - Mobile executives have said they do n’t have the resources or spectrum to offer 4 G LTE service , although the company now offers the slower HSPA+ quasi-4 G religious service .

Several minority groups and working class unions have voiced support for the flock .

Kohl questioned AT&T ’s promises that the deal would countenance it to flesh out its 4 thousand LTE rollout from 80 percentage of the U.S. universe to 97 percentage . Much of the T - Mobile spectrum AT&T would postulate does n’t cover rural areas , he order .

The expansion of a “ novel coevals of cellular phone sound service not yet deployed six year from now is plainly too high-risk and uncertain to justify this merge under antimonopoly laws , ” he wrote .

Kohl also question if Sprint Nextel could remain in business sector if the deal is sanction .

Three popular members of the House of Representatives , John Conyers Jr. of Michigan , Ed Markey of Massachusetts and Anna Eshoo of California , also wrote a letter to the DOJ and the FCC Wednesday , calling on the agencies to cautiously review the quite a little .

“ We believe that AT&T ’s accomplishment of T - Mobile would be a worrisome slow-witted step in federal public policy — a curtailment from nearly two decades of advertise competition and open market to espousal of a duopoly in the wireless market place , ” they wrote .