NEW YORK (Bloomberg) - Motorola Inc., the biggest US mobile-phone maker, forecast an unexpected loss and said profit fell 84 percent last quarter as customers fled to Apple Inc. and Samsung Electronics Co.

Motorola dropped 22 percent in New York trading. That's the biggest decline in almost seven years and puts the stock at its lowest since September 2003, when Chris Galvin was still running the company.

Phone sales will drop "significantly" in the next three months after plunging 38 percent in the fourth quarter, Greg Brown said yesterday in his first earnings call as CEO. Motorola phones led by the Razr 2, the sequel to the best-selling model, have failed to lure consumers from Apple's iPhone, Samsung's Sync camera handset and Nokia Oyj devices.

"The first quarter will be a challenging quarter," Mr. Brown said. "We've got to refresh the product portfolio as soon as we can."