New transport secretary Grant Shapps is unlikely to halt the planned rail fare increase for 2020, which is expected to be announced next week.

The Welwyn Hatfield MP, who was appointed to the cabinet in July, said it was "tempting" to advocate for lower fares.

"But we all know that money is needed to invest in our railway too," said Mr Shapps.

"A bit of a vicious circle, but I intend to find the long-term solution."

Season tickets for a year to London are predicted to increase by £115 in St Albans, £148 in Royston and £109 in Stevenage on January 1, 2020, according to calculations by the Campaign for Better Transport this week.

An increase of £100+ in Herts is down to ticket prices being linked to a way of calculating inflation called the Retail Price Index (RPI) instead of the much lower inflation rate called the Consumer Price Index (CPI).

A predicted increase by three per cent in RPI - due to be announced on Wednesday, August 14 - would therefore mean fares going up by the same percentage points, which the previous transport secretary Chris Grayling said was "difficult to justify" and "should be a thing of the past".

"But there is still no end in sight to these exorbitant increases that will cost commuters dearly from January," said Darren Shirley, chief executive of Campaign for Better Transport.

"The government should commit now to January's fares rise being linked to CPI and a comprehensive package of reforms to rail fares should follow after the Rail Review completes in November."

Mr Shapps said he was looking forward to the rail review, currently being carried out by Keith Williams, which will be published in the autumn.

"Trains running reliably and on time really shouldn't be beyond a modern advanced economy," he told this newspaper.

"It will doubtless take time, but this is what we must deliver," he said,

"In the end the problem is that, despite passenger numbers doubling since the system was privatised over 20 years ago, getting the trains to actually run on time hasn't been nearly central enough.

"So I'm convinced we need a system where there's a proper single point of responsibility. And that means combining the best of what's led to our railways being the busiest in history, with a new laser-like focus on the punctuality of our trains."