Scottish families say end of Universal Credit uplift "means choosing between heating and eating"
The "shameful'' cut to Universal Credit will push 22,000 Scottish children into poverty, charities have warned.
A ÂŁ20 uplift to the benefit that was introduced at the start of the coronavirus pandemic ended on Wednesday, leaving recipients of Universal Credit ÂŁ1,040 worse off a year.
Child poverty campaigners are calling for the UK Government to reverse its decision to reduce the payment "before the damage mounts irreparably''.
A report by the Child Poverty Action Group (CPAG) in Scotland estimates that a further 22,000 children will be in poverty in Scotland as a direct result of the cut, while the Save the Children charity says it will affect more than 360,000 families.
Kirsty McKechnie, a project manager for CPAG, said: "It is shameful that the Prime Minister has pressed ahead with today's extraordinary cut to ordinary family incomes - ripping over a ÂŁ1000 a year from already inadequate family budgets.
"The UK government really must think again and reverse this cut before the damage mounts irreparably. In the meantime, it's vital that families are supported to claim the other financial benefits they are entitled to.
"We know that too many are missing out on council tax reduction and on disability benefits for example, while others are unaware that their children may be entitled to free school meals and school clothing grants.''
Kirsty McCann, a mum of three from Maryhill, told Forth 1: "ÂŁ20 is a bill, it's my gas and electricity for the week.
"It's breakfast for my kids for the week.
Calling for Chancellor Rishi Sunak to "reinstate the ÂŁ20 lifeline'', the head of Save the Children in Scotland, Claire Telfer, said "The UK government's decision to go ahead with this cut will devastate families in Scotland.''
She added: "People we work with tell us they've been relying on this ÂŁ20 lifeline to buy essentials like food and clothing for themselves and their children.
"Without it, tens of thousands more children are facing a cold and hungry winter. And we know the impacts of childhood poverty can last a lifetime.
"It's astonishing that UK Government ministers have chosen to inflict the most significant social security cut in memory at the same time that families are grappling with a cost-of-living crisis; Inflation, increases in energy prices, fuel shortages and tax hikes are all taking their toll on family finances.
"For many, this will be a significant catastrophe of falling income and rising costs. The UK Government has a duty to protect families from hardship and not add to it.''
As the cut comes into effect, Citizens Advice Scotland (CAS) has urged people affected to seek advice on how they can manage financially.
CAS chief executive Derek Mitchell said: "Increasing the value of Universal Credit at the beginning of the pandemic was the right thing to do and was a lifeline for millions of people across the UK and around half a million people in Scotland.
"Our fear is reducing the value of these payments will push lots of people into impossible financial choices in the coming weeks and months.
"This is particularly worrying as energy bills have increased and prices have risen in the shops. It's a perfect storm for people.''
Labour's Shadow Scottish Secretary Ian Murray said: "The Tories are inflicting untold damage on communities with this disgraceful cut as the PM laughs about it.
"There was never any justification for this - but it is all the more dangerous to press ahead with these plans as a cost of living crisis hits.
"The Tories have given up any pretence of caring about the most vulnerable in our society. This cut will go down in history as a particularly shameful act from a cruel and uncaring government on working people.''
A UK Government spokesperson said: "We've always been clear that the uplift to Universal Credit was temporary.
"It was designed to help claimants through the economic shock and financial disruption of the toughest stages of the pandemic, and it has done so.
"Universal Credit will continue to provide vital support for those both in and out of work and it's right that the Government should focus on our Plan for Jobs, supporting people back into work and supporting those already employed to progress and earn more.''