Transport for London is considering phasing out coins and notes next year and replacing them entirely with contactless payments - such as Oyster Cards.
TFL says it would help save millions of pounds. But thousands of people still rely on cash to travel around on London's buses every day, and critics warn it could put jobs and safety at risk.
Rags Martel reports:
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A police officer who spent six days crawling the London Marathon in a gorilla costume has finally completed the 26-mile route.
The victim of a "violent and sustained attack" on the top deck of a London bus has been named as Archie Sheppard.
Transport for London has made the badges and accompanying cards permanently available after a successful trial in autumn last year.