A £20 fine is not enough to stop persistent fare dodging in London - according to the Liberal Democrats.
More than £60m is lost every year due to fare evasion
From Sunday any passenger found without the correct tickets on buses, trains, tubes and the DLR will now be fined £20 instead of £10.
Lib Dem Geoff Pope called for an increased penalty in order to make it cost effective to take people to court.
About 90,000 fines are issued every year to people travelling without a ticket on the Tube and buses.
Mr Pope said "It is vital that the Mayor and Transport for London target persistent offenders and, when they are caught, stop them getting away with fare dodging by giving a false name and address."
More than £60m is lost each year from fare evasion on the Tube, London buses and the Docklands Light Railway.
Mr Livingstone said the increased fine would send out a clear message that "freeloading will not be tolerated".