RadioShack confirmed rumors of a house-branded wireless service today with the launch of no-contract phones running on Leap Wireless International’s network.

The prepaid service, reports of which leaked three weeks ago, could provide RadioShack with a way to cash in on the growing market for low-cost wireless service.

RadioShack sells wireless service from AT&T, Verizon Wireless and Sprint, and will now offer prepaid service under its own brand, RadioShack No-Contract Wireless.

RadioShack’s plans start as low as $25 per month for feature phones, ranging to $60 on the high end for smartphone users. The $25 plan includes 300 voice minutes with unlimited text messages and Internet access. RadioShack is also offering feature phone users a $35 plan with 1,000 voice minutes, plus all-you-can-eat SMS and Internet access.

Smartphone users are being offered a $50 plan with unlimited calls, domestic text messaging and 1 GB of full-speed data before throttling kicks in. Smartphone customers on the $60 plan get 2.5 GB of data before being limited to slower speeds, with unlimited minutes and international text messaging. Both smartphone plans also offer access to Leap’s Muve Music service.

Leap’s contract with RadioShack marks the first time it has leased out its Muve Music service to a third party. The move follows comments from company executives earlier this year that Leap was considering licensing the popular music service, offered through its Cricket Communications prepaid brand. On Sunday, Cricket added access to Muve Music to all of its Android plans.

RadioShack’s prepaid smartphones will be bundled with a 8 GB memory card capable of storing up to 6,000 songs. The first smartphone for the service, the Huawei Mercury Ice, hits shelves tomorrow. The Android phone sells for about $150 and comes equipped with a 1 GHz processor, 4-inch display and 8-megapixel camera.

Huawei is also the manufacturer for RadioShack’s second device, the Pillar, a $40 feature phone with a physical keyboard and camera. RadioShack plans to launch two additional devices by the end of this month.

Leap has a limited network footprint and depends on a roaming deal with Sprint for nationwide coverage. The operator said last month it would not make a full payment to Sprint for the use of its network. It owes Sprint $75 million this year under the terms of a contract it signed in 2010.

A Leap spokeswoman said the dispute with Sprint would not affect the RadioShack deal.