BMW’s US arm is buying US auto parts suppliers from American auto partmaker AO, including its US-based BMW Group, according to a document seen by Reuters.

The company has bought American parts suppliers for its carmaker BMW and its auto parts division BMW Advanced Technologies, which supplies parts to Mercedes-Benz, Audi, Porsche, Lexus and Nissan.

The documents seen by the Reuters news agency, dated April 10, 2018, show that the deal was approved by the US Federal Motor Carrier Safety Administration on March 26.

It says the companies will be working together on the joint development of technologies for autonomous driving and self-driving systems.

The deal follows similar deals with American carmakers such as General Motors, Ford and Chrysler.

The BMWs move follows the acquisition of a third American supplier by BMW in November, when it bought US-listed auto parts supplier Automotive Parts & Equipment Corp for US$3.3 billion.

BMW acquired AO in 2014.BMW, the world’s second-largest carmaker, has seen its sales fall over the past five years, partly because of the impact of a drop in oil prices.

In a statement, the company said it was buying American parts from both American and foreign suppliers and developing its own vehicle-safety and mobility technologies.BMWs first global partnership with AO was announced in 2018, but the two companies are not connected.

The announcement of the deal in a statement by the BMW Group said the two parties “will cooperate in the development of advanced and advanced self-healing, autonomous driving, self-diagnosis, advanced vehicle diagnostics and mobility solutions”.

The deal is part of a trend of US carmakers acquiring more and more European suppliers in recent years, with several of those acquisitions being based on AO’s US-owned parts.

In February, BMW bought German carmaker Daimler for US $4.8 billion.

Daimler has also purchased UK-based vehicle-sensing and vehicle-assist software provider Infotech from German car giant Volkswagen for US £1.7 billion, and also announced a joint venture with Mercedes-AMG to develop autonomous driving software.