T-Mobile will develop 5G-capable networks in dozens of U.S. markets — including its two largest — by the end of the year, CTO Neville Ray announced Tuesday at Mobile World Congress.

"This year, we'll be building 5G across 30 cities in the U.S.," Ray said during a press conference at Mobile World Congress in Barcelona. Ray said the company is already installing 5G equipment as it continues to build its LTE network in the country.

The carrier previously said it planned to introduce mobile 5G service in 2020, behind expected debuts from its U.S. rivals. AT&T intends to deploy mobile 5G in 12 markets this year, while Verizon plans to introduce fixed wireless 5G in up to five markets later in 2018.

Sprint, meanwhile, this week announced plans to deploy Massive MIMO technology in six markets in preparation for mobile 5G service next year.

Ray, however, argued that because T-Mobile's service won't exclusively rely on high-band spectrum, the company will be able to deploy a comprehensive 5G layer in time for the debut of 5G consumer devices next year.

"I'd rather commit our effort to something much more meaningful," Ray said.

He said the service would utilize the 600 MHz spectrum secured in an auction last year along with spectrum in the 28 GHz and 39 GHz bands. Ray added that the company would begin offering 5G "in the markets where it counts" — the first four announced cities were New York, Los Angeles, Dallas and Las Vegas.

T-Mobile CTO Neville Ray at MWC in Barcelona announcing the carrier plans to deploy 5G networks in 30 U.S. cities this year (Photo: Andy Szal)

Ray also praised announcements Monday that federal regulators would work to free more mid-band spectrum and hold auctions in the 28 GHz and 24 GHz bands.

Although he said the millimeter wave spectrum utilized by his rivals would be unable to support a broad 5G network in the U.S., those bands nonetheless hold "great capability" in dense, urban environments, Ray said.

"The U.S. industry needs more spectrum."