A FORMER UK transport minister has condemned party colleagues' campaign on Scotland's railways as "totally unrealistic populism", accusing them of promoting "irrelevant" policies .

Tom Harris, who held the Westminster post under both Tony Blair and Gordon Brown, said Scottish Labour had avoided explaining how its demands for rail fares freezes could only be funded by tax hikes.

Heaping pressure on beleagured leader Kezia Dugdale, Mr Harris also compared the party's 'People's Scotrail' campaign with the rise in populist politics typified by Donald Trump and UKIP, dismissing calls for a nationalised operator as "an irrelevant solution to a very complicated problem".

The comments come a month after the former Scottish Labour leadership candidate, one of his party's most stridently Unionist figures north of the border, called for Holyrood to be given total control of the railway infrastructure in Scotland.

But Labour said its MSPs had "led the way on exposing the chaos facing ScotRail passengers" and had "successfully held the SNP government to account".

Scottish Labour has made the railways its key weapon to attack the SNP Government in recent months, complaining about delays, overcrowding and ticket prices on the network and calling for both the current ScotRail franchise holder, Dutch firm Abellio, to have its contract terminated.

The industry has said it is going through major enhancements with the network being electrified and rolling stock and stations improved.

The Government announced as part of its recent budget that fares would rise but come with a free week's travel for monthly and season ticket passengers backed by £3million, which it said was of greater value than the hike.

But Mr Harris said: "I'm irritated by any political party trying to get short term advantage from the railway industry.What has really irritated me is the campaign for rail fares freeze. This year, 2016, is meant to be the year we're turning our backs on populism. It's really done enough damage. "But there's little more populist than a rail fares freeze, which is totally unrealistic.

"Presumably Labour doesn't want cash to be cut from other parts of the railways budget and they know it doesn't come from the Scotrail.

"In essence what they're saying is a freeze should be paid for by taxes going up. It's an incredibly short-term proposal."

The former Glasgow MP also described nationalisation as a "red herring" and said claims the network would not face similar delays and problems if it was state-owned as "just cobblers".

He added: "People would just get angry at the Government instead of operator. Network Rail are also a nationalised operation and yet they're responsible for more delays than the operator. It's about management not ownership and nationalisation is an irrelevant solution to a very complicated problem."

One senior industry insider described Labour's campaign as "deeply cynical", accusing them of having only one policy.

The source added: "Rather than standing outside stations handing out flimsy dossiers that stand no scrutiny whatsoever, they would be better served talking to the industry about what could actually make a difference.

"Quite apart from anything else, it's just rubbish politics. Around 7500 people work on the railway. Those people have been told time and time again by Labour they are failures. That will be doing them the type of long term damage they can ill afford."

Transport minister Humza Yousaf said: “For a party that claims to be in favour of a publicly-owned ScotRail it does beg the question why Labour sat on their hands and chose not to stop franchising when they had a golden opportunity to do so."

A Labour spokesman said: "We will always put passengers first. Regular travellers are fed up with delayed, overcrowded and cancelled trains. "After the year they have endured, we believe all passengers deserve a break with a freeze on rail fares in 2017. This policy has been very popular with passengers. In the long-term we want to move to a publicly owned People's ScotRail, and we've seen with the East Coast Main Line that public ownership can deliver better results.

"We have also seen the Labour Mayor of London Sadiq Khan introduce a freeze on many fares in the Transport for London network for four years."