The proposal, which is subject to a public consultation, is the latest step in Transport for London’s campaign to encourage drivers to use only their official site when entering the congestion charge zone.
In recent months there’s been growing concern about the conduct of third-party sites which often charge more than the official rate for entering the zone.
In some instances site operators have also failed to register vehicles with TfL, incurring penalties for drivers.
TfL has already secured an Advertising Standards Authority ruling against one site and has worked with Google to limit the ability of unofficial sites to advertise on the search engine. Refusing to accept payment from such sites would make it harder for them to operate.
A 6-week public consultation is now open and runs until 12 September 2014.
Garrett Emmerson, TfL’s Chief Operating Officer for Surface Transport, said: “We continue to work hard to protect our customers from unofficial third party websites that charge extortionate prices for non-existent services.
“By blocking unauthorised payments we will be making a further step towards removing the threat of these sites.”
Views are also being sought on a proposal to replace the current SMS (text message) payment option with a new smart phone app.
Following the consultation TfL will prepare a report for the Mayor who will then decide whether to implement the proposals.
