General Motors Corp. (GMGMQ) said Friday its purchasing chief, responsible for the company's $100 billion parts operation, is leaving as thousands of auto suppliers struggle to stay afloat.

Bo Andersson, GM's group vice president of Global Purchasing and Supply Chain, is leaving to "pursue other interests," the auto maker said in a statement. A person familiar with the situation said Andersson left on his own accord to take a job that will be announced as soon as next week.

Known for his aggressive, outspoken style, Andersson has been a key figure in keeping parts flowing to the company as it navigates through bankruptcy court. Many suppliers face their own financial crisis amid sinking demand for vehicles and pressure to cut costs from struggling auto makers.

Andersson, who ushered in a system of global purchasing at GM, embraced the current crisis and saw it in part as a way to squeeze out lingering inefficiencies in the company's massive supply system. Andersson's departure came as a surprise to many suppliers and those within the company.

GM, like its rivals, have been forced to walk a careful line between cutting enough costs without straining suppliers so much they're forced out of business.

Some of the country's largest auto parts suppliers are teetering on the edge of bankruptcy as continued production cuts erode their financial stability. In May, Visteon Corp. and Metaldyne Corp. filed for Chapter 11 protection.

GM, which filed for bankruptcy June 1, is moving to further consolidate its supply base as part of a restructuring being overseen by the U.S. government.

Suppliers plan to ask the Obama administration for up to $10 billion in new aid to forestall a crisis triggered by the bankruptcies of GM and rival Chrysler LLC. Supplier trade groups are mainly requesting that the government guarantee between $8 billion and $10 billion in loans industrywide so banks will have the confidence to lend to parts suppliers.

"Bo has made tremendous contributions to the development of our global purchasing and supply chain strategy as we've globalized our product line portfolios and manufacturing footprint," GM Chief executive Fritz Henderson said in a statement.

Andersson joined GM in 1987 as a manager at Sweden-based Saab AG. Before becoming vice president of global purchasing and supply chain in 2001, he headed purchasing at GM Europe. Most recently, Andersson was appointed a group vice president in 2007.

-By Sharon Terlep; 248-204-5532; sharon.terlep@dowjones.com.