BMW chief Norbert Reithofer says that co-operation with other car manufactures is integral to his company's strategy to cut costs amid the global recession.

He told the annual shareholders meeting today (14 May) that BMW would extend its purchasing cooperation with Daimler without compromising its own independence. The two companies embarked on a joint purchasing and parts strategy earlier this year and might be prepared to share a platform for future small cars.

Daimler CEO Dieter Zetsche said earlier this week that the two carmakers were examining much closer links. Historically, engineers at BMW and Daimler opposed swapping technologies but the need to cut costs is now overriding that resistance.

Reithofer told BMW shareholders that 2009 would be a "challenging" year and that it was "much too early" to predict an end to the auto industry slump. BMW was sticking to its goal of earnings before interest and taxes (EBIT) of 8-10% of sales by 2012.