Rail commuters in the east of England could be spending more than 15pc of their salary on season tickets next year, transport campaigners warn.

Annual rail fare rises are based on July's retail price inflation (RPI) figures, which are expected to come in at just under three per cent when they are published today by the Office for National Statistics.

The Campaign for Better Transport has predicted the increase would see the annual season ticket fare for Norwich to London Liverpool Street will increase from �6,900 this year to �7,314 by the end of next year – a rise of �414.

For those travelling between Norwich and Diss, a price hike of �96 is predicted, while the season ticket fare between Norwich and Cambridge could go up by �234 from �3,900 to �4,134.

The predicted fare for Norwich to Cambridge is calculated to be 15.61pc of a person's average salary.

The government wants to raise fares by three points above inflation for the next three years in an attempt to switch the onus for funding the railways from the taxpayer to passengers.

The total cost of running the railways is about �11bn a year, of which �7.2bn, or 65pc, comes from fares. The aim is to increase this to 75pc, while getting the industry to cut its costs.

Stephen Joseph, chief executive of the Campaign for Better Transport, said: 'If the government sticks by its policy, rail fares will rise three times faster than salaries. With the economy flat-lining, this is untenable.

'The government knows they can't continue to hit commuters – that's why they've postponed the road fuel duty escalator. Now they need to do the same for rail users.

'If rail fares are allowed to gallop ahead like this, many commuters will soon being paying 10 per cent or more of their salary just to travel to work. This is no way to stimulate the economy.'

Nationally, a series of demonstrations are being held at more than 40 railway stations across the country today. including Waterloo, Euston and Kings Cross, Birmingham New Street, Newcastle upon Tyne, and Crewe.

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