Dish Network Corp. said on Tuesday that it would not make a new offer to buy No. 3 U.S. wireless provider Sprint Nextel and focus instead on its tender offer for Clearwire Corp.

"While Dish continues to see strategic value in a merger with Sprint, the decisions made by Sprint to prematurely terminate our due diligence process and accept extreme deal protections in its revised agreement with SoftBank, among other things, have made it impracticable for Dish to submit a revised offer by the June 18th deadline imposed by Sprint," Dish said in the statement.

This is the latest turn in a take-over battle that started on April 15 when Dish - led by its chairman and founder, Charlie Ergen - offered to buy Sprint for $25.5 billion in a challenge to Japan's SoftBank Corp.

Known for his aggressive tactics in deal-making, Ergen is looking to expand into the wireless market as its traditional pay-TV business has been maturing.