´óÏó´«Ã½

Southeast Asian ride-hailing company Grab has partnered with start-up nuTonomy which last month launched a driverless taxi trial in Singapore.

Grab users will be able to use the app to book nuTonomy cars for driverless rides in a small district of the city only.

The cars still have a backup drivers.

The announcement comes as car and technology companies around the world step up their experiments with self-driving cars.

The big ride-hailing competitor Uber, which is working with car maker Volvo in the US, started a trial with self-driving cars in Pittsburgh in August, albeit also still with a backup driver who can take control should technology fail.

Lyft has joined forces with US giant General Motors, whose chief executive earlier this month predicted driverless cabs in as little as 5 years.

NuTonomy started a limited public trial of a driverless taxi in August in Singapore, and says it hopes to have as many as 100 autonomous taxis operating in the city-state by 2018.

Karl Iagnemma, chief executive of nuTonomy, told the ´óÏó´«Ã½ that the partnership with Grab will "allow us to expand our public pilot by integrating it with the Grab app".

He said: "People can use the Grab app to call one of our cars, and it's going to be very similar to hailing a Grab car today except that that car will be driven by our software - not by a human driver," he explained.

Aside from ride-hailing or taxi companies, carmakers are also working on autonomous driving technology.

Google has for years been working on its driverless Google car, also pushing US legislators to update the legal framework for a future of self-driving vehicles.