Abu Dhabi-based Aabar Investments has purchased 40 percent of Daimler AG's stake in electric-car start-up Tesla Motors Inc, with the aim of launching a joint venture, Aabar said on Monday.
In May, Daimler acquired an equity interest of just under 10 percent in Tesla.
Tesla is one of the biggest players in the burgeoning electric car sector, while Aabar is viewed as a spearhead investor for the emirate of Abu Dhabi in non-energy assets.
"This investment allows Daimler and Aabar to leverage their shared interest in the development of low-CO2 drive systems," the companies said in a statement.
In March, Aabar purchased a 9.1 percent stake in Daimler, saying then it would pursue joint strategic projects.
Aabar shares were down 2.8 percent after the statement. Daimler was up 0.74 percent.
Aabar is an investment company controlled by the International Petroleum Investment Company, which is wholly owned by the Government of the Emirate of Abu Dhabi.
IPIC is one of the investment vehicles used by the Abu Dhabi government to invest oil income. Abu Dhabi pumps most of the oil produced by the United Arab Emirates, the world's third-largest oil exporter.