General Motors Corp. has notified Suzuki Motor Corp. it plans to sell off its Suzuki shares as part of its restructuring efforts, a move that could result in the dissolution of a 25-year capital tieup between the two firms, sources said Sunday.

GM is Suzuki's top shareholder with a 20 percent stake. The market value of the shares GM holds is about 270 billion yen, and Suzuki will consider buying the shares itself, according to the sources.

The sale is expected to prompt Suzuki to consider selling shares it holds in GM Daewoo Auto & Technology Co., the sources said. Suzuki holds an 11 percent stake in the South Korean automaker.

Suzuki said, however, the sale would not immediately lead to dissolution of its capital tieup with GM, which dates back to 1981.

GM has been planning plant closures and other restructuring measures. It has been losing U.S. market share to foreign rivals due partly to sluggish sales of sport utility vehicles and pickup trucks amid high gasoline prices.

With the planned sale of Suzuki shares, GM is expected to concentrate its small car business on GM Daewoo, the sources said.

In October, GM sold a 20 percent stake in Fuji Heavy Industries Ltd. Toyota Motor Corp. acquired an 8.7 percent stake to become Fuji's biggest shareholder.

GM currently holds a stake of nearly 8 percent in Isuzu Motors Ltd.