The talks are nearing conclusion and a contract is due to be signed in September, it added.

Continental declined to comment on what it described as speculation.

Carmakers BMW, Daimler and Volkswagen bought HERE for 2.8 billion euros ($3.22 billion) in 2015 from Finnish telecoms group Nokia as they push ahead with investments in self-driving cars.

Last year Chinese digital mapping company NavInfo , Tencent and Singapore's sovereign wealth fund GIC took a 10 percent stake in HERE, with the German carmakers pledging to reduce their own stakes.

But HERE needs more capital to expand its network of high-precision maps and has been in talks with other investors. Talks with US carmaker Ford are most advanced, Manager Magazin said, without being more specific.

A spokesman for Ford Europe declined comment on speculation.