BMW chairman, Norbert Reithofer, has said he has not ruled out building engines for other manufacturers.

"We are thinking about it," he told the German news magazine, Focus.

BMW already produces engines for the Mini in a joint project with PSA Peugeot Citroen. The four cylinder joint engine project is also being considered for use in other small BMW models. "We thought: wouldn't that be a good engine for other BMW models?" said Reithofer.

Cooperation with other manufacturers is considered 'a highly efficient method', without which many projects could not be realized. BMW is currently considering which companies it could join with for future cooperations. The cooperation would not have to be for a complete vehicle.

Daimler chairman, Dieter Zetsche, recently confirmed that the two companies are in talks about possible joint engine development.