Slammed by a deep decline in auto sales, General Motors is expected to announce cutting of thousands of salaried jobs and closing of additional plants, a media report said on Tuesday.

GM Chairman and Chief Executive Rick Wagoner is scheduled to outline the plan to employees, the Wall Street Journal reported.

"This is real, hard stuff," one person briefed on the plan told the paper. "It not only assures our survival, but will make us a radically leaner, more focused company with much lower fixed cost."

Along with cost-cutting measures, GM may announce new steps to improve liquidity, such as a dividend cut or reductions in executive pay, these people said.

A person familiar with GM's plans was quoted as saying the moves that will be announced are aimed at putting the auto maker in a position to 'generate sufficient liquidity on our own'.

The measures were approved by GM's board in a meeting on Monday morning, people familiar with the matter said.

A GM spokesman declined to comment further.

The announcements, the Journal said, will follow weeks of rising uncertainty for the No.1 US auto maker by vehicle sales. The company's stock price has plunged to the lowest level in last 50 years.

Its shares fell 54 cents, or 5.4 per cent, to $9.38 at 4 pm at New York Stock Exchange composite trading on Monday.

GM and other auto makers have been hurt by a big drop in US vehicle sales this year and a shift in consumer preferences away from trucks and sport-utility vehicles to small cars and other more fuel-efficient models.

Most of the moves GM is expected to announce, the paper said are likely to be aimed at reducing the company's heavy reliance on trucks for most of its sales in North America, and ramping up production of cars and other fuel-efficient vehicles as quickly as possible.