"It remains to be seen whether every carmaker develops their own system, or whether you bundle your efforts," Witter said in a conference call with journalists.

"We want to have access to a self-driving system and we are speaking with relevant players. It is very expensive to develop and others are already well advanced. Waymo is one of them," Witter said, adding that no final decision had been taken.

Witter said sharing the carmaker's electric cars platform MEB with Ford was theoretically possible, although the carmaker is currently focussed on rolling out the electric vehicle technologies among its own brands.

(Reporting by Edward Taylor; Editing by Michelle Martin)