Sprint Nextel announced Thursday it would be selling nearly all of its wireless communication towers to TowerCo for $670 million in cash.

Under the terms of the deal, TowerCo will take over the operating and maintenance of approximately 3,300 towers that use Code-Division Multiple Access and Integrated Digital Enhanced Network technologies.

The two companies have also entered into a long-term lease that allows Sprint to run its cellular and WiMax networks from these towers. The deal is expected to close in 90 days.

"By leasing rather than owning these network facilities, we can better focus on our core business of providing communication services to consumers, businesses, and government customers," said Bob Azzi, Sprint's senior VP, field engineering and operation, in a statement. "Significantly, this transaction provides Sprint Nextel with additional liquidity which gives us greater flexibility in managing our company."

While Sprint is currently the third-largest mobile operator in the U.S. market with about 53 million subscribers, the company has seen a steady decline in revenue and profits since the 2005 acquisition of Nextel. The wireless operator has long been rumored to be an acquisition target.

The company has seen a bit of a rebound lately, particularly with the hot-selling Samsung Instinct. Sprint is expected to announce an improved customer turnover rate for the second quarter.

TowerCo was founded in 2004 by Tailwind Capital, and manages more than 8,000 communications towers.

"These are great towers concentrated in large metropolitan markets throughout the United States and will benefit as wireless communications continue to grow," said Richard Byrne, TowerCo's CEO, in a statement.