Sadiq Khan has been accused of reneging on his flagship election promise that London commuters would not “pay a penny more” in transport fares if he became mayor. It comes after Mr Khan, who was elected as mayor in May, revealed on Wednesday that his pledge to deliver a freeze for all fares would only cover single and Pay As You Go fares.

Mr Kahn’s election manifesto vowed: “Londoners won’t pay a penny more for their travel in 2020 than they do today.” But travelcards, daily “caps” on Oysters and contactless card fares will not be covered, meaning hundreds of thousands of passengers are likely to see their fares increase with inflation.

Speaking at a weekly meeting of the London Assembly, Mr Khan said: “My promise to freeze Transport for London fares is there but obviously I can’t make the government do what I am doing,”

“If all fares were frozen including those set by the DfT [Department for Transport] TfL would have to compensate the DfT for lost revenue.”

He added that it was “for the DfT to make sure they fulfil a promise that I made to Londoners”.

Caroline Pidgeon, a Liberal Democrat London Assembly member, said: “Mayor’s freeze promise broken today. Will not apply to travelcards. Not what he said in campaign.”

She added: “Sadiq Khan’s manifesto specifically said that Londoners won’t pay a penny more for their travel in 2020 than they do today.There were no ifs, or buts, in that statement.

“The reality is that many Londoners will see their travelcards rise over the next few years.  What we have found out today feels like a very early broken promise from London’s new Mayor.”

The Labour mayor’s fares freeze pledge became a key battleground in the election contest and Mr Khan’s team sent out press releases attacking Zac Goldsmith, his Conservative rival in the race, over his “secret plan to hike fares for all Londoners”.

Tory group leader Gareth Bacon added: “Just four weeks after the election the Mayor’s flagship policy has been thrown out of the window.

“By raising Travelcard prices by inflation and breaking his biggest promise he is turning his back on those who showed faith in him.

“Hundreds of thousands of commuting Londoners use Travelcards, and thus will never see this freeze.”

London government professor expert Tony Travers said: “Londoners will without doubt have formed the impression that the fares commitment meant a freeze for all fares for four years. A freeze only affecting pay as you go fares is a very different thing.”

A spokesman for Mr Khan told The Independent: “Sadiq is delivering on his promise to freeze fares for Londoners and  today he confirmed that millions of passengers using TfL bus, Tube, Overground, DLR and tram services will see no increase in their fares while he is Mayor. The fares freeze will benefit 96 per cent of commuting Londoners.

“Sadiq only has the power to set the fares on TfL services, which is why he will continue to push the Government to follow his example by freezing their own fares ‎ and transferring suburban rail services to TfL as quickly as possible so that even more passengers benefit from his fares policy.”