A political row has broken out over who is to blame for rising train fares despite the Mayor of London’s pledge to freeze the cost of travel until 2020.

Sadiq Khan, made the announcement on Transport for London (TfL) ticketing during his election campaign.

On Tuesday (January 3) national rail fares increased by an average of 2.3 per cent, causing some opponents to accuse Mr Khan of breaking his promise.

The Mayor’s office has said Mr Khan only has the power to set fares on TfL services and the government sets national rail fares in agreement with the private train operating companies.

This includes the price of travelcards, travel on rail lines including Southern, Southeastern and South West trains and daily and weekly caps.

The Mayor’s Office added TfL fares will be frozen for the next four years, so the price of travelling by bus or tram or other TfL services will remain at the level it was in 2016.

Mr Khan said: “As someone who has relied on London’s public transport system all my life, I’m hugely proud we’re freezing fares for millions of Londoners and making our city a better and more affordable place to live and work.

“As I said in my manifesto, we had to put a hold on the rocketing fares Londoners faced under the previous mayor and our landmark TfL fare freeze will save an average household £200 over the next four years.”

“While I have kept my promise on TfL services, Londoners will rightly be furious on the same day, the government have allowed the private train companies to increase their fares by more than two per cent – and on some journeys up to five per cent.

“Given the train companies’ woeful record of delays, cancellations and overcrowding, it is scandalous the government are letting the train companies off the hook again.

“The government must match my fares freeze next year.”

The leader of the Conservative Greater London Authority group, Gareth Bacon, accused Mr Khan of breaking his promises and letting down commuters across London.

Mr Bacon said: “Just days into the New Year and Londoners are already feeling the pinch of Sadiq Khan’s broken promises.

“He said you will not pay a penny more in 2020, but just like all the other promises his fare freeze is not worth the paper it is written on – and ordinary working Londoners are paying the price.”

Liberal Democrat London Assembly member, and former mayoral candidate, Caroline Pidgeon said: “Sadiq Khan’s manifesto specifically said Londoners won’t pay a penny more for their travel in 2020 than they do today.

“There were no ifs, or buts, in the statement.

“The mayor has frozen the fares he controls and the government should do the same.”

Transport secretary Chris Grayling argued the increase in fares was justified, and insisted an average of 97p in every £1 paid in train fares was reinvested back into the railway.

He said: “Thanks to action by the government on train ticket prices, wages are growing faster than regulated fares.

“This commitment to cap regulated fares in line with inflation will save annual season ticket holders an average £425 in the five years to 2020.

“To improve services, we are investing more than £40 billion into our railways.

“This will provide passengers with better trains that are faster and more comfortable.

“We are delivering the biggest rail modernisation programme for more than a century, providing more seats and services.

“We have always fairly balanced the cost of this investment between the taxpayer and the passenger.”