NEW YORK, Nov 30, 2007 (AFP) - Motorola said Friday its chief executive Ed Zander was stepping down as the US mobile phone maker faces shrinking market share amid stiff global competition.

The resignation of Zander, 60, will take effect January 1, but he will remain chairman until the annual meeting of stockholders in May 2008, the company said in a statement.

Motorola Inc. named Greg Brown, 47, currently the company's president and chief operating officer, as CEO. Brown, a veteran of high-tech companies, joined Motorola in 2003.

The company gave no reason for the departure of Zander, who took the top position in January 2004.

Zander said he wanted to spend more time with his family.

Motorola, once the world's second-largest mobile phone maker, has undertaken restructuring and slashed jobs as it battles eroding market share.

The company has posted a series of poor quarterly earnings and has seen its industry share slip to third place, behind Nokia of Finland and Samsung of South Korea.

Motorola barely turned a profit in the third quarter of this year, due to flagging mobile phone sales.

Investors applauded the shuffle at the top, driving shares up 1.53 percent to 15.89 dollars around 1548 GMT as the overall market posted moderate gains.