Leaked documents have shown plans to cut a number of London bus routes and reducing a number of others.
One of the routes at risk is the 48 from Walthamstow Central to London Bridge.
Darryl Chamberlain from 853London.com, who unearthed the documents, said: "It's going to have a terrible effect on people who are least able to pay for public transport and least able to fight back."
Transport for London say that due to the number of other routes and different forms of transport available, many buses are not being used.
Mayor of London Sadiq Khan told ITV London: "What we're doing is making sure is that in those areas where there's high demand for buses they have those buses there, but in those parts of London where there is a surplus of buses, for example, we know in Oxford Street, in Park Lane, in Kingsway, during some hours there a one, two, three hundred buses that are going down those roads, not being used, running empty.
"We're going to move those buses from central London to outer London."
TFL say there will be a full public consultation before any changes are made.