TORY backsliding will stop the Scottish Government from scrapping the controversial bedroom tax until at least May 2020, it is claimed.

The SNP committed to ending the benefit cut as part of its manifesto.

Under the plan, the Scottish Government was to make changes to Universal Credit payments from spring next year.

But Social Security Secretary Angela Constance says the Department for Work and Pensions (DWP) has pushed this back until 2020 “at the earliest”.

She said: “Last year we came to an agreement with DWP that would enable us to end the bedroom tax through Universal Credit, meaning that no one would be penalised as a result of the positive moves we are taking in Scotland. It is now extremely disappointing that the DWP has put the brakes on this decision, delaying the necessary changes to the Universal Credit system until May 2020 at the earliest.

“This is yet another example of the UK Government going back on agreements in place to the detriment of those already finding it hard to get by.”

According to the Scottish Government, as many as 70,000 households are currently affected by the bedroom tax.

Eight in ten of this group includes someone with disabilities.

At present, Holyrood uses discretionary housing payments to mitigate the support cut at a cost of £50 million a year, but this can only be done when eligible households make an application.

The DWP was expected to devolve responsibility for the housing element of Universal Credit to the Scottish Parliament from next spring, allowing officials to stop the penalties.

However, the Westminster department says this date was never confirmed and more work must be done before the change is put in place. A spokesperson said: “The changes we are introducing to facilitate transition on to Universal Credit and address concerns around the first payment period have been agreed in the UK Parliament.

“These measures will make a positive difference for Universal Credit claimants across Scotland and the rest of the UK and must be our priority.

“We continue to work constructively with the Scottish Government on this and have been very clear throughout that the potential date of 2019 was subject to detailed feasibility.”

The statement comes after the Scottish Government released a letter from Constance to UK Secretary of Work and Pensions Esther McVey.

It was sent last month in the days after Neil Couling, director general of Universal Credit, advised officials of the delay.

Constance wrote: “Abolishing the bedroom tax is an important manifesto commitment and a pledge the Scottish Government has repeatedly made in successive programmes for Government.

“I am therefore disappointed and surprised to learn that your department has not ringfenced our changes to be implemented in 2019 or allocated any dedicated resources to deliver this commitment.

“We have, it appears to me, been essentially re-prioritised in a queue of existing and new work, much of which would appear to post-date the Scottish Government’s policy. “

Calling for the DWP to take “active steps” on the matter, the MSP for Almond Valley went on: “While I do accept that your department will have many priorities, the transfer of these powers from the UK to the Scottish Parliament is a commitment made by politicians from all parties and now law under the Scotland Act 2016.

“I am becoming increasingly concerned that your department is not consistent in displaying either the willingness nor urgency to deliver on what is very much a joint programme of activity over the coming years.”