The deal, which is worth up to £15 million, will see Cubic Transportation Systems (CTS) adapt London's contactless ticketing system to work with existing systems in other cities. It helped TfL introduce the Oyster card and then adapt barriers to support contactless cards, but also create a backend that is capable of combining millions of swipes into easy payments. It's now possible that passengers in Sydney, Brisbane, Vancouver and Chicago, where CTS also operates, will see some TfL technology in their own metro systems.

While commuters all over the world are set to benefit from the new system, Londoners won't miss out. Sadiq Khan says that the money earned from the new licence will be used to freeze fares across Transport for London services over the next four years and is just the start of a number of planned agreements.

"I made a firm commitment to sell Transport for London's expertise around the globe," says Khan. "We will use the income from those deals for further investment in new infrastructure and to freeze TfL fares."