-By Kenneth Hein, Brandweek

NEW YORK Wendy Clark, a prime force behind the rebranding of AT&T, is stepping down as svp, marketing for the telecom giant.

A statement issued by the company stated that it is beginning a search for her replacement: "The AT&T brand is iconic in the communications industry globally and the company is one of nation's largest advertisers. We plan to conduct an extensive search for candidates to lead AT&T's advertising and brand management efforts as the company continues to expand, domestically and globally."

Like Clark, the new svp will report to Cathy Coughlin, AT&T senior evp and global marketing officer. Clark's last day was not known.

Sources said that Clark wasn't interested in relocating. AT&T is relocating its headquarters from San Antonio to Dallas.

Clark, the former svp, director of client service at Omnicom Group's GSD&M Idea City, Austin, Texas, joined AT&T in 2004. Shortly afterward she was charged with rebranding the company, formerly known as SBC, which changed its name to AT&T in 2005 after it bought the former "Ma Bell," capping off several mergers and acquisitions. AT&T also bought Cingular Wireless and, in a somewhat controversial move, rebranded it as AT&T as well.

At the Association of National Advertisers conference in October, Clark said, "After the [nine] mergers. We knew we had to evolve ourselves." The new AT&T received a huge boost from its association with Apple's iPhone, which Clark called "a steroid for our rebranding."

AT&T spent $1.86 billion on media in 2007, per Nielsen Monitor-Plus. Omnicom-owned BBDO in New York is AT&T's lead agency.

"We appreciate Wendy Clark's leadership during a period when the company significantly expanded its operations and successfully launched the new AT&T brand. We wish her all the best in the future," said AT&T in a statement.

Clark is the second major client marketing executive to step down in as many days, following the disclosure yesterday that Jim Stengel, global marketing chief of Procter & Gamble, would be succeeded by P&G exec Marc Pritchard on Aug. 1.