Londoners face 20mph speed limits on main roads in the city centre and £100 fines if they break the rules, under new plans unveiled today.
Transport for London wants to roll out lower speed limits on the majority of roads inside the capital's congestion zone.
This would mean 5.5 miles of London's streets would carry a £100 fine for drivers caught speeding - more than the standard £60 penalty fare.
The plans for red routes were revealed today with a second phase proposed to reduce all speed limits in suburban London by 10mph by 2024.
London drivers are likely to be furious about the new charges, which come on top of £12.50 toxic air fees introduced earlier this year.
Transport for London wants to roll out 20mph speed limits on all roads inside the capital's congestion zone (map shows areas affected)
London Mayor Sadiq Khan is putting the proposals out for consultation today in a bid to get them put into place by May 2020.
The main roads affected in central London include the Albert and Victoria Embankments, Millbank and Borough High Street.
Mayor Sadiq Khan (pictured on May 17) is putting the proposals out for consultation today in a bid to get them put into place next year
Despite not being in the congestion zone, the Aldgate Gyratory would also be reduced to 20mph if the plans are given the green light.
The measures also include raised pedestrian crossings at 'high risk' locations near Embankment, Tower Hill and the Tate Britain.
They are designed to act as speed bumps so pedestrians are safer when they cross the road.
If the initial changes are brought in, transport officials will push for 93 miles of roads in Greater London to reduce their speed limits over the next five years.
Several Londoners have already slammed the plans, claiming they are redundant on busy roads that are so congested with traffic you often can't get above 20mph anyway.
Manchester City Council was forced to scrap a 20mph scheme that cost taxpayers £1.7million after they found it made no difference.
It was abandoned in 2017 - five years after it launched - when figures revealed speed limits in some areas had actually gone up.
Steve McNamara, of the Licensed Taxi Drivers Association, hit out at today's proposals, telling the BBC: 'Most people would love to go as fast as 20mph in the middle of London.
'Average traffic speeds are 6mph in the centre - we have the lowest traffic speed of any city in Europe, barring Moscow.
'I can't think of anywhere in central London it would make any difference at all, at least in the daytime. Those roads are all at a virtual standstill.'
Steve Garelick, who is union GMB's regional spokesman, fears the speed limits could see night time drivers and moped riders suffer.
He also claims statistics do not always suggest 20mph speed limits reduce the number of road deaths.
Drivers in London have already hit out at the plans on social media branding them 'idiotic'
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