T-Mobile is urging federal regulators to block Verizon’s planned spectrum acquisition from SpectrumCo, a joint venture formed by Comcast, Time Warner and Bright House Networks. Verizon’s pending purchase could be worth $3.9 billion and would help the company build out its nationwide LTE network. In a filing late Tuesday, T-Mobile said the Federal Communications Commission should block the deal because it would place an “excessive concentration” of wireless spectrum in Verizon’s hands, reports the Associated Press. The AWS bands that Verizon is looking to acquire uses the same frequencies that T-Mobile uses for its HSPA+ network. T-Mobile claims that the nation’s No.1 carrier already has a large amount of spectrum and does not need any more, and T-Mobile can “quickly, more intensively, and more efficiently” put the spectrum to use compared to Verizon. MetroPCS, the nation’s fifth-largest wireless provider, also urged the FCC to block the deal, claiming both parties had not provided enough information to prove that the acquisition is in the public’s best interest. Verizon and SpectrumCo hope to close the deal by the middle of this year.