General Motors Co. raised eyebrows Friday when it said it aimed to sell new cars on eBay Inc.'s (EBAY) online marketplace, but the ecommerce giant appears to have been caught off guard by the auto maker's announcement.

EBay said it was excited about a "potential" new program to help GM dealers sell the products over the Internet, but the company suggested that GM's announcement was perhaps pre-mature.

"At this time, no plans have been finalized with General Motors. We hope to support GM's new company and vision going forward," said eBay in a statement.

General Motors Co., which emerged from bankruptcy protection on Friday, announced at a news conference in Detroit a series of sweeping changes to its management structure, adding that it would realign sales and marketing functions.

Chief Executive Fritz Henderson also said at the event that GM is testing a new online auction system with eBay that will enable customers to bid on actual vehicles just like they do in an eBay auction, including the option of choosing a predetermined "buy it now" price.

Under the eBay partnership, dealers would continue to book revenue from vehicle sales because they would handle final delivery of cars and trucks, Chief Executive Fritz Henderson said. "We're working with dealers on this," he said. "Not around them."

When pressed for details on the program, Henderson said GM would reveal more in the coming weeks. The company, he said, picked California as a launch state because it's a large auto market in which GM would like to improve its performance.

But when later asked about eBay's reaction to his earlier comments, Henderson said GM "got a little out ahead" of the deal with its announcement.

More than 30,000 U.S. franchise and independent dealers already use eBay as a complementary sales channel for their businesses. Several auto makers, including General Motors, also list certified pre-owned cars on eBay's Motors marketplace.

But an eBay spokesman said new car sales on eBay Motors represent a small percentage of total sales. GM's new initiative, if successful, would increase the number of new cars available through the Internet site.

The spokesman declined to comment as to whether eBay was talking to other car makers on plans similar to the one GM mentioned Friday.

-By Scott Morrison, Dow Jones Newswires; 415-765-6118; scott.morrison@dowjones.com

-By Sharon Terlep, Dow Jones Newswires; 248-204-5532; sharon.terlep@dowjones.com

(John Stoll contributed to this report.)