He said lives and livelihoods were hanging in the balance as the world “dangled at the edge of this economic precipice.”Mr Brown, former MP for Kirkcaldy, spoke out as the UK Government pressed ahead with plans to end the £20 top-up payment to people on Universal Credit.
The cut takes effect next month.
He described the move as “more morally indefensible than anything I have ever witnessed in politics.”
He said: “For 75 years the British welfare state has provided the safety net for families in dire need but, after October 6, the last line of support for families will not be the welfare state but food banks.
“Britain's poor can no longer rely on social security for the minimum they need to prevent their descent into extreme poverty.
“Their lifeline is now charity. “He added; “The £20 a week is the difference between a breakfast and starting the day hungry, and between school clothes and children going ill-clad and ill-equipped.
“Fuel poverty will force a choice between heating and eating
“And added to the country’s 2000 food banks will be baby banks .clothes banks, bedding banks and hygiene banks.”
He added: “Never have I see a Government act so callously and with so little concern for the consequences in human suffering.”Mr Brown, who is a patron of charities in his former constituency has appealed to local businesses to make good the damage done by the withdrawal of the £20.”
The former Prime Minister said already almost 50% of families with three or more children are below the poverty line as are nearly 70% of the unemployed.
He warned that the £20 cut to Universal Credit will further increase child poverty by 200,000 and overall family poverty 500,000.
Mr Brown said the welfare state is no longer even attempting to discharge its promise made in the Beverage Report of 1942 to abolish the five evils of squalor, want, disease, ignorance and idleness.
“No longer will social security, as was promised then, take the fear - and the shame - out of need.” he said. “. I can tell Ministers from my experience that hope is being destroyed in the places they never deign to visit and there is desperation in the faces they never see.
“Twenty years ago we promised we would abolish child poverty in a generation .
“Now all we can do is to offer charity to prevent destitution. Marcus Rashford spoke for millions when he said that his community had little in material goods but what they lacked in money they had in compassion for each other.
“And that’s what they will now have to rely on: the poor having to come to the aid of the poorest. – and all people of conscience, with a shred of decency, from local businesses to national charities. stepping up to fill the gap in empathy and moral fibre that this Government has wilfully opened up.”