DETROIT (AP) _ General Motors Corp.'s top executives Tuesday defended the No. 1 automaker's failure to move its U.S. market share back above 30 percent since strikes last summer virtually shut down its North American production for several weeks.

``We're not intending to shrink the company,'' Chairman Jack Smith said at a news conference to announce GM's new electronic commerce initiative.

GM's share of the U.S. market through July was 29.3 percent, compared with 29.9 percent for the first seven months of 1998. July's share was only 28 percent. GM's goal is to get more than 30 percent of the market this year, a goal that appears increasingly unlikely to be reached.

Smith said GM was working hard to increase its share, but that ``the market's so strong it's impossible to produce more vehicles.''

The U.S. market is headed toward a record year of around 16.7 million cars and light trucks, well ahead of the nearly 16.1 million new vehicles sold in 1986.

Wagoner said he was optimistic about GM's fortunes in the United States.

``Some of the underlying trends are good,'' he said. ``Retail share continues to go up month by month. The reaction to our new products is good. So I feel like the fundamentals are there.''

Smith also said he does not plan to retire soon, and declined to say if there was a retirement date set in his contract.

GM announced last week that it had signed an agreement with Daewoo Group of Korea to begin exploring joint automaking ventures. But Smith said a deal would not come soon.

``There's a lot of work to do there,'' he said.