STOCKHOLM (Reuters) - A Volvo Cars joint venture has won approval to begin hands-free testing of its software for self-driving cars on Swedish highways, partner Veoneer said on Monday.

FILE PHOTO: A self-driving Volvo electric truck with no cab called Vera is seen during a presentation in Berlin, Germany, September 12, 2018. REUTERS/Emma Thomasson/File Photo

Veoneer said the Zenuity joint venture’s software for Level 4 autonomous driving - the second highest level - would be tested in a Volvo car by trained drivers with their hands off the steering wheel at a maximum speed of 80 kilometers per hour (50 miles per hour).

The venture is striving to keep up with larger rivals in the race to develop self-driving vehicles.

U.S. companies are leading the pack, with Google’s Waymo last year winning the first approval to test cars without safety drivers on Californian public roads.

General Motors’ Cruise has said it is ready to deploy a self-driving car with no manual controls, while Germany’s BMW and Audi have also secured testing rights.

Securing permissions has got tougher after an accident involving a Volvo car that Uber was using to test its own self-driving software. Uber last month resumed limited testing on public roads.

Zenuity has been running tests in Sweden to collect data to develop autonomous functionalities and sensors, while Volvo has been carrying out separate tests to gather data to improve driver experience and study driver behavior.

Veoneer Chief Technology Officer Nishant Batra said the approval to do real-life tests was “essential for gathering important data and test functions”.

“It is a strong proof-point for the progress of Zenuity’s self-driving capabilities,” he said.

Veoneer spokesman Thomas Jonsson said it was too early to say when Zenuity could potentially test without a safety driver.

Zenuity, formed by Volvo and Veoneer in 2017, is expected to have its first driver assistance products on sale by 2019 with autonomous driving technologies shortly afterwards. Volvo and its Chinese parent Geely are customers.

Volvo has goals of delivering self-driving cars sometime after 2021 and deriving a third of its sales from fully autonomous cars by 2025.

Documents obtained from the Swedish Transport Authority showed Volvo in September secured the right to test self-driving cars at 80kph and the permit removed a previous condition that a driver has at least one hand on the steering wheel.

The cars Volvo was testing were “for the development of fully autonomous vehicles” and it was using outside parties and test drivers, a Volvo spokesman said.

A top Level 5 vehicle, or fully autonomous vehicle, will be able to navigate roads without any driver input in all conditions.

Volvo teamed up with Baidu last year to use the Chinese company’s autonomous software to develop a Level 4 car.