The huge Chinese carmaker is mulling taking its BAIC Motor unit public, and last week Dow Jones Newswires reported Daimler, the parent of Mercedes Benz and Smart, was weighing taking a 10 percent share in the company.

"BAIC is planning an IPO, we will support that intention," said Zetsche.

"In that context of course, we are negotiating what the framework would be."

Daimler already has joint ventures with BAIC to help the German firm build and market its cars and trucks in China, now the world's largest auto market.