The work and pensions secretary, Amber Rudd, plans to lodge a formal complaint with the UN about the damning report on austerity in Britain by its special rapporteur on extreme poverty, Philip Alston.

Rudd will argue that Alston is politically biased and did not do enough research. The minister is seeking guidance from the Foreign Office on the best way to respond after Alston compared her department’s welfare policies to the creation of Victorian workhouses.

Alston quoted the 17th-century philosopher Thomas Hobbes to warn that unless austerity was ended and welfare cuts were reversed, millions of poorer Britons faced lives that would be “solitary, poor, nasty, brutish and short”.

The 21-page report said the government appeared unwilling to debate the impact of its austerity policies since 2010, which it said were “in clear violation of the country’s human rights obligations”.

Alston accused ministers of “window dressing to minimise political fallout” by insisting the country was enjoying record lows in absolute poverty, children in workless households and unemployment.

The “endlessly repeated” mantra about rising employment overlooked that “close to 40% of children are predicted to be living in poverty two years from now, 16% of people over 65 live in relative poverty and millions of those who are in work are dependent upon various forms of charity to cope,” he said.

The report will be formally presented to the UN Human Rights Council in Geneva on 27 June.

The government believes Alston, a New York-based human rights lawyer, could not credibly have reached his conclusions after only an 11-day trip to the UK. Last November he visited nine towns and cities in England, Scotland, Northern Ireland and Wales, holding town hall meetings and visiting poverty-related charities and organisations including food banks and youth programmes.

Rudd is said to be particularly frustrated by Alston’s accusation that the government was responsible for the “systematic immiseration of a significant part of the British population”. She also believes Alston ventured off his beat by making criticisms about cuts to police numbers and legal aid.

In a statement, the government said his report was “a barely believable documentation of Britain based on a tiny period of time spent here” and “a completely inaccurate picture of our approach to tackling poverty”.

Either side of his trip, Alston worked for several months with a team of legal scholars and staff from the office of the UN high commissioner for human rights researching austerity in the UK.

According to the footnotes to the report, they analysed information from three government ministries, the Scottish and Welsh governments, the National Audit Office and the Equalities and Human Rights Commission. They also examined reports from organisations including the Institute for Fiscal Studies, the Joseph Rowntree Foundation and the OECD, and received more than 300 written submissions.

Labour said the report should be a “source of shame” to ministers and urged them to “end their state of denial”. Margaret Greenwood, the shadow work and pensions secretary, said: “This report is a shocking indictment of the brutal cuts to social security introduced by Conservative-led governments since 2010 and the deeply flawed, punitive system that they have created.”

The DWP said: “We take tackling poverty extremely seriously, which is why we spend £95bn a year on welfare and maintain a state pension system that supports people into retirement. 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 and we introduced the national living wage, so people earn more in work.”

Groups with years of experience examining poverty in the UK backed Alston’s conclusions. Campbell Robb, the chief executive of the Joseph Rowntree Foundation, said: “There can be no moral justification for failing to act on this report.”

Alison Garnham, the chief executive of Child Poverty Action Group, said Alston had “exposed the government’s refusal to acknowledge the scale of child poverty in the UK. We can reduce child poverty in the UK – we’ve done it before. But it will require a willingness from government to first see the problem and then to deliver a strategy for solving it.”