"The project is worth an estimated $125 million," the spokesman said, adding that production is to start in 2010, at a rate of 50,000 cars a year.
M300 is the codename for a new small car that will go on sale later this year.
GM Uzbekistan already makes such cars as Captiva, Epica, Tacuma, Nexia, Matiz, Lacceti and Damas.
General Motors owns a 25% interest in the company. In October 2005, the 500,000th vehicle rolled off the assembly line.
In 2007, 170,000 cars were produced and almost 140,000 during the first nine months of 2008.