Saudi tycoon Prince Alwaleed bin Talal and his Kingdom Holding invested US$500m in General Motors in the US auto giant's IPO last week, the company said.

Alwaleed and Kingdom took a 1% stake in GM when the automaker returned to the public share markets with a $20bn-plus initial public offering on 18 November, Kingdom said in a statement.

"The decision of Kingdom Holding Company and Prince Alwaleed to invest in GM was based on the global strength of General Motors brand, the relatively attractive offering price, and the company's growth prospects in Brazil and China," it said, according to AFP.

The statement did not say how much of the GM stake would be held by the prince privately and how much by Saudi-listed Kingdom.

"We cannot disclose that information at this time," Kingdom spokesman Hazim al-Dosary told AFP.

Kingdom, about 95% controlled by Alwaleed, is a major investor in major global companies like Citigroup, News Corp. Apple and Walt Disney.

It also owns and manages prominent luxury hotels around the world.