CONTROVERSIAL plans to merge British Transport Police with Police Scotland face being delayed indefinitely, it has emerged.

The proposals have come under fire in recent months amid claims they amount to “an act of vandalism”, with fears a full merger would not be possible by next year’s delivery date.

Now the Scottish Government has confirmed it has agreed to “review the timetable”, but rejected suggestions this signalled a delay of up to two years.

Police Scotland’s Deputy Chief Constable Iain Livingstone insisted “unresolved issues” meant the merger could not go ahead by April 2019 “without compromising public safety”.

He added: "Planning for the integration of British Transport Police continues and we will be working closely with BTP, the rail industry and other partners over the coming months to determine a new date.

"The priority for Police Scotland, as always, is to ensure that we continue to deliver the highest possible standards of service and that all of our communities, including people who work on and use the rail network, are kept safe."

But critics said the SNP Government had “failed to do the basic work to identify and plan for the risks and implications of their latest centralisation”.

Scottish Liberal Democrat justice spokesman Liam McArthur MSP said: "We warned SNP ministers not to repeat the mistakes they made in pushing through the Police Scotland centralisation.

“They rejected constructive calls for implementation of the BTP merger to be delayed, giving the impression the timetable was generous, or even a luxury. Now they have been found out.

"Today's decision underlines the Scottish Government’s substandard planning and lack of business case. It should also signal a halt to this merger for the foreseeable future."

Scottish Conservative shadow justice secretary Liam Kerr said it was time the plan was “derailed altogether”, labelling it “an unpopular move that virtually nobody is in favour of”.

And Scottish Labour justice spokesman Daniel Johnson said the delay "reopens the debate about whether this foolish and misguided merger should go ahead at all".

Ministers said the delay would allow for “enhanced engagement with officers, staff and their representatives on key issues, including pay and conditions”.

But they refused to put a new delivery date on the plans, insisting a “detailed re-planning exercise” would iron everything out over the coming months.

It comes after sustained criticism of the proposals in recent months, with former Scotland Office minister Lord Foulkes arguing they would "jeopardise an effective fight against terrorism". BTP officers have also spoken out against them.

It is understood concerns over IT form part of the reason for the setback – as well as the suspension of Assistant Chief Constable Bernard Higgins, who was the main Police Scotland point of contact and is now facing criminal allegations.

Justice Secretary Michael Matheson said the Scottish and UK governments were working together to ensure the legislation passed by MSPs last year is implemented “as effectively as possible”.

He added: “The benefits of a single command structure and improved access to the full range of capabilities of Police Scotland will be delivered for railway policing, providing an enhanced service to both the rail industry and travelling public.

“While much has been achieved so far, we want to ensure a seamless transition which delivers continuity of service for rail users and staff.”

He said that while the delay was disappointing, it would “provide all partners with the opportunity to enhance the process of engagement, in particular with officers, staff and their representatives on key issues”.

Mr Matheson insisted the Scottish Government remained committed to delivering on its triple lock guarantee to protect the jobs, pay and pensions of BTP officers transferring to Police Scotland.

A BTP spokeswoman said: "We remain committed to ensuring any proposed merger goes ahead as smoothly as possible, both for our own staff and for rail passengers in Scotland."