“We take tackling poverty extremely seriously, which is why we spend £95 billion a year on welfare and maintain a state pension system that supports people into retirement,” a spokesman for the Department for Work and Pensions said on Wednesday. That works out to around $120 billion.

“All the evidence shows that full-time work is the best way to boost your income and quality of life, which is why our welfare reforms are focused on supporting people into employment,” he added.

Britain’s unemployment rate is at its lowest level since 1974, government figures show. But Mr. Alston said the “repeated response” that more people are employed overlooks several “inconvenient facts”: nearly 40 percent of children are predicted to be living in poverty two years from now; 16 percent of people over 65 live in relative poverty; and millions of those who are working are dependent upon charities to cope.

The rapporteur acknowledged that the government had taken action on some issues raised in his preliminary report. He singled out in particular the introduction of a uniform poverty measure that accounts for food insecurity and a delay to the rollout of a benefits system known as universal credit, which has pushed thousands of people under the poverty line.

“That program will be improved by plans to provide more time to repay advances, to reduce debt payment limits and to reduce extreme penalties,” he said. “But, for all the talk that austerity is over, massive disinvestment in the social safety net continues unabated.”