General Motors Corp., continuing its aggressive push into East bloc markets, said Thursday it reached an agreement valued at nearly $1 billion to supply car parts to the Soviet Union's largest automaker.

The pact calls for GM, the world's biggest carmaker, to provide engine management emissions control subsystems and components to Volga Auto Works based in Togliatti, 700 miles southeast of Moscow.These subsystems help the automobile regulate its fuel system to improve emissions levels. The components include fuel injectors and related devices. GM said the systems initially will be placed on two Volga models.

In addition, GM said it and Volga will discuss forming a joint venture to make catalytic converters, air pollution-control devices, in the Soviet Union.

GM said the agreements enable it "to become the first American-based auto manufacturer in modern times to establish a working relationship with the Soviet auto industry."

The Detroit-based automaker has been the most aggressive of the Big Three U.S. carmakers in exploiting the recent liberalization of Eastern bloc markets.

In late May, GM announced that it expects to assemble cars in East Germany, the first U.S. manufacturer to do so. The company also is planning an auto assembly and components-manufacturing venture in Hungary.

GM said Volga intends to use the GM technology to equip its vehicles to meet current and expected worldwide emissions standards. Engine management systems for several other Soviet passenger cars may be added to the program within a few years.