A Fife politician had demanded the Conservatives halt plans for the accelerated roll out of Universal Credit, amid claims it is pushing families into poverty.
Mid Scotland and Fife MSP Alex Rowley has contacted every MP in the UK asking for their support to stall the scheme.
Following a meeting in Glenrothes, when he heard about the problems it is causing, he now has severe concerns that families are hurtling into debt.
Mr Rowley has written to the Secretary of State for Work and Pensions and Scottish Conservative leader Ruth Davidson to challenge them to halt the roll-out.
He highlighted particular concerns about the six-week waiting period for payments at the start of the process.
Evidence from Citizens Advice Scotland suggests this is resulting in people ending up with rent arrears and forcing them to rely on crisis grants and desperately needed aid from food banks.
The Scottish Labour deputy leader said: “I have heard first hand from people in Glenrothes and across the region some of the issues around the roll out of Universal Credit and there is a very real concern that the system is leaving many in poverty and debt.
“Universal Credit is supposed to make access to social security less complex, and to further support people into work.”
But, he argued: “This cannot be the case if it is leaving people without the vital support they need and drives some to food banks simply to survive.”
He said the six-week waiting period for payments at the start of the process was particularly concerning, resulting in people ending up with rent arrears, and forcing them to rely on crisis grants and food banks for the very basic necessity of feeding themselves.
“The accelerated roll out of Universal Credit must be halted until these problems can be resolved.
“If the system puts more people in poverty or debt, or even increases the risk of these, then it should not continue in that form.
“A Labour government working for the many, not the few, would act immediately to end the worst excesses of the Tory government’s changes, and would rebuild and transform our social security system,” he added.
