Commuters between Glasgow and Edinburgh will be made to fork out an extra £114 each year as ScotRail prepares to increase fares.

Regulated peak fares will increase by 2.8% from January 2, and will apply to season tickets and anytime singles and returns.

It is determined by the July 2019 Retail Price Index (RPI), which is used to set the rate of increases on ScotRail services.

Those travelling between Glasgow and Edinburgh will see a £114 increase on their annual season tickets, with the price rising from £4,084 to £4,198.

ScotRail commercial director Lesley Kane said the Scottish Government decides how much passengers pay for fares.

"Eighty-five per cent of our revenue comes from fares set by the Scottish Government, which decides how much our customers pay," she said.

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"The money generated from fares is reinvested back into Scotland's railway, including £475 million under Abellio in new and upgraded trains and improved punctuality, so that we can give our customers the service they expect and deserve."

A Scottish Government spokeswoman said although a fares increase is unwelcome, moves to cut or freeze fares would hit the public purse.

"We are committed to ensuring that rail fares are affordable for passengers and taxpayers across Scotland," she said.

"We have capped increases where we have influence, making fares 20% cheaper on average than in the rest of Great Britain.

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"While any fare increase is unwelcome, calls for measures such as fares cuts or a fares freeze underestimate the impact of these on the public purse.

"Two-thirds of the cost of running the railway is already met through Scottish Government subsidy, with the remainder through rail passenger revenues.

"Any change to rail fares could, therefore, have a significant impact on the taxpayer."