The move by South West Trains has angered passenger groups and union leaders.

The increases will hit passengers travelling into London between 10am and noon.

Passenger Focus said the rise in off-peak fares, which kicks in on May 20, was "unexplained and unfair".

Chief executive Anthony Smith said: "These large increases are unjustified. They have the effect of extending the peak throughout the whole of the morning.

"They have been introduced without consultation and are a blow to passengers who value an affordable walk-on fare."

Gerry Doherty, leader of the TSSA rail union, said it was "daylight robbery".

Last week, South West Trains' owners Stagecoach revealed plans to pay shareholders a £700million dividend.

The move meant that founder Brian Souter and his sister Ann Gloag landed a £175m windfall.

"Dick Turpin was famous for robbing stagecoaches," said Doherty. "But today it is passengers who are being held to ransom by the Stagecoach owners."