Sprint Nextel will lay off about 4,000 employees and close about 125 retail outlets after it suffered a net loss of more than 100,000 customers in the fourth quarter of 2007, the company said Friday.

The layoffs and other cost-cutting measures are expected to save the company $700 million to $800 million a year, the company said in a news release.

The company reported a net gain of 500,000 subscribers through wholesale channels, growth of 256,000 Boost Unlimited users and net additions of 20,000 subscribers within affiliate channels. These gains were offset by net losses of 683,000 post-paid subscribers and 202,000 traditional prepaid users.

At the end of the year, Sprint had 53.8 million subscribers, including 40.8 million customers of its traditional post-paid service.

In addition to the layoffs, to come in the first half of the year, Sprint plans to close about 8 percent of its company-owned retail locations and eliminate more than 4,000 third-party distribution outlets, the company said. Sprint now has 20,000 total distribution points, including nearly 1,400 company-owned retail locations.

Sprint will announce its full fourth-quarter results on Feb. 28.