T-Mobile USA said it may be interested in selling anywhere from 3,500 to 5,000 of its cellphone towers -- a sale that could bring upwards of $1 billion, according to industry newsletter RCR Wireless.

The money could come in handy after the fourth largest carrier in the country spent about $4 billion on new spectrum to deploy high-speed 3G services.

"We've been saying all along that T-Mobile should consider selling its towers," said Mark DeRussy, an analyst at Raymond James & Associates. "Considering T-Mobile wrote a pretty big check for the last auction, this could help pay for that."

Often times, towers are owned by a third party that can then lease space to multiple carriers to save on expenses.

RCR said the carrier's German-based parent company, Deutsche Telekom, revealed this information during a conference call Thursday detailing financial results.

T-Mobile USA said it added 901,000 new customers in the fourth quarter for a total of more than 25 million customers.

The Bellevue company's net income for the quarter was $179 million, down from $1.79 billion in the third quarter and $3 billion in the fourth quarter 2005. The lower net income resulted primarily from non-cash income tax benefits in both of the previous quarters. T-Mobile USA's total revenue grew to $4.5 billion in the quarter from about $4 billion a year earlier.