The former prime minister said the withdrawal of the £20-a-week uplift on 6 October could not come at a worse time for struggling households, which face the prospect of rising food and energy costs.
“I have never seen a government act so callously and with so little concern for the consequences of their actions on the poorest in our society,” he said.
Writing in the Guardian, he also called the reduction “more economically illogical, socially divisive and morally indefensible than anything I have witnessed in this country’s politics”.
The universal credit uplift was introduced at the start of the pandemic and was initially intended to last a year, before being extended by another six months.
However, politicians and charities have urged the government to make the change permanent, warning that its removal in the current financial climate could push hundreds of thousands more people into poverty.
A new report by Citizens Advice predicted that as many as 1.5 million people could be plunged into hardship this winter by what it called a “disastrous decision”. It also estimated that up to 600,000 universal credit claimants are concerned about not being able to afford food if the change goes ahead.
Dame Clare Moriarty, the organisation’s chief executive, said: "The government has shown in this pandemic that it’s willing to support people through hard times.
"With a cost of living crisis under way, it must reverse the disastrous decision to cut this lifeline."
Ms Davidson recently told ITV that the decision was “bad politics”, adding that “it’s the wrong thing to do for people on low incomes”.
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