FRANKFURT, Germany (AP) — Automaker Daimler says its Chinese partner BAIC Group has taken a 5% equity stake, a move Daimler said reinforces the cooperation between the two companies.

Daimler, maker of Mercedes-Benz cars, said Tuesday that BAIC acquired the stake through a fully-owned subsidiary, Investment Global Co. Ltd.

Daimler and BAIC have worked in a strategic partnership since 2003 and in 2013 Daimler took a stake in BAIC Motor, a listed subsidiary of BAIC. Daimler currently holds 9.55% of BAIC Motor's shares.

Daimler's biggest shareholder is Chinese investor Li Shufu, chairman of carmaker Geely, with 9.7%. Kuwait's Sovereign Savings Fund has 6.8%.