London Tube and bus day travelcards rise by up to 74%
Day travelcard users on London's Underground and buses face price hikes of up to 74% from 2011.
The Zone 2-6 Travelcard will be withdrawn meaning passengers wishing to continue using travelcards will have to buy a Zone 1-6 version instead.
This would mean a peak hours ticket rise from £8.60 to £15.
Tube bosses said they were simplifying fares, but watchdog London TravelWatch said outer London residents and tourists would be worst affected.
"We are very concerned that these inflation-busting fares will price people off public transport," said Jo deBank from London TravelWatch.
"Everyone will be hit, but it appears that infrequent users, those in outer London and visitors and tourists will be hit particularly hard."
Labour's London Assembly transport spokeswoman Valerie Shawcross called the fares "a kick in the teeth" for Londoners.
"This was slipped out quietly but Londoners won't fail to notice this huge increase when they are buying their tickets in January," she added.
Transport for London (TfL) said Zone 2-6 travelcards were used by fewer than 6,000 passengers a day, including just 300 people during peak times.
It said passengers should use its Oyster pay-as-you-go system instead.
"It is far cheaper to use Oyster pay as you go, with outside zone one fares ranging from £1.30 to £2.50," a TfL spokeswoman said.
"We would advise passengers travelling outside Zone 1 infrequently to use Oyster pay-as-you-go or if travelling frequently to check out our range of weekly and monthly season tickets."
On Wednesday, London Mayor Boris Johnson said he would not have to raise Tube fares more than his already stated 2% above inflation and free travel for under-18s would remain in place.
TfL used July's Retail Price Index (RPI) of 4.8% when reviewing fares, which would mean a 6.8% average rise in fares from 2011.
Meanwhile, Tube travellers suffered fresh delays on Thursday morning because of a cracked rail.
The Jubilee Line - used by more than 500,000 passengers a day - was suspended through central London during the morning peak period, with other lines becoming packed as commuters used other routes.