Telecom giant AT&T plans to lay off 1.5 percent of its employees, primarily in management, in an effort to streamline its operations, the company announced Friday.

AT&T had about 310,000 employees at the end of 2007, meaning the layoffs would affect about 4,650 workers. The layoffs are the "next step" in streamlining company operations in an effort to operate more efficiently after recent mergers between parent company SBC, the old AT&T and BellSouth, the company said in a filing with the U.S. Securities and Exchange Commission.

AT&T expects its total number of employees to remain stable in 2008 "as the company hires additional employees to support growth areas," AT&T said in the filing.

The company did not announce a time line for the layoffs in its SEC filing. The streamlining effort is focused on jobs that don't interact with customers, the company said.

"This initiative is part of the company's move from a collection of regional companies to one AT&T focused on customers," AT&T said in the filing.

The layoffs mean AT&T will take a one-time charge of US $374 million during the first quarter of 2008. AT&T is scheduled to announce its first-quarter earnings Tuesday.

AT&T reported a net income of $3.1 billion for the fourth quarter of 2007. It's revenue for the quarter was $30.3 billion.