General Motors Co. CEO Frederick "Fritz" Henderson stepped down Tuesday after the board determined that the company wasn't changing quickly enough.
Chairman Ed Whitacre Jr. said at a hastily called news conference that he will serve as interim CEO, and an international search for a new CEO and president is planned.
Whitacre thanked Henderson for his work during a period of challenge and change, but said it is time to accelerate the pace of rebuilding the largest U.S. automaker.
The resignation comes just eight months after Henderson, 51, replaced former chairman and CEO Rick Wagoner, who was ousted March 29 by the Obama administration's government's auto task force.
Henderson has been with GM his entire career and was the government's choice to run the beleaguered company after Wagoner left. Whitacre, picked by the government in June to be chairman of the new GM, is considered an industry outsider, having run AT&T Inc. for 17 years.
Whitacre and the board have become increasingly active in the company's decisions, at times challenging some of Henderson's decisions. In November, the board voted to abandon plans to sell GM's European Opel unit. That reversed an earlier option favored by Henderson to sell it to a consortium led by Canadian auto parts supplier Magna International Inc.
"Based on the determination of the board and the pace of the change in the company, it was determined that it was best to initiate a change in direction," spokesman Chris Preuss said.
An Obama administration official said in a statement that "this decision was made by the Board of Directors alone. The Administration was not involved in the decision."
Henderson replaced Wagoner a few months before GM entered bankruptcy protection and led the company through a painful government-led and court-supervised reorganization.
With the government's help, the company emerged from court protection in just 40 days cleansed of massive debt and burdensome contracts that would have sunk it without federal loans.
Henderson continued to downsize the automaker after its emergence from bankruptcy. He sought to scale down GM to just four core brands: Chevrolet, Cadillac, Buick and GMC.
While he has largely succeeded in that goal, attempts to sell the company's other brands have hit obstacles. Earlier this week, Swedish luxury sports car maker Koenigsegg Group AB backed out of a deal to buy GM's Saab brand. GM said Tuesday it has some interested bidders but will wind down Saab if nothing materializes by the end of the year.
GM also is winding down Pontiac and was successful in winning a tentative sale of Hummer to a Chinese construction machinery maker.
However, Henderson's bid to sell Saturn to race car mogul Roger Penske fell through and the brand is now liquidating.
Henderson was scheduled to be the keynote speaker at the Los Angeles Auto Show on Wednesday. GM Vice Chairman Bob Lutz will now deliver the address.