Green & Black's offers taxi rides in exchange for a selfie

Luxury chocolate brand Green & Black's is offering Londoners the chance to take a ride in a black cab for free, while indulging in its newly-launched Truffle and Praline bars.

Green & Black's offers taxi rides in exchange for a selfie

Specially-branded Green & Black's cabs are roaming the streets of London until 28 October. 

People are being encouraged to hail one and pay with a selfie, which they can then post on Instagram before boarding, tagging Green & Black's. 

Once in the cab, they can sit back and enjoy a bar of the new chocolate.

The activation has been devised with PR agency Golin.