Iain Duncan Smith’s controversial welfare reforms are facing a United Nations investigation over possible violations of disabled peoples’ human rights, it has been reported.

Officials will visit the UK “in the next few months” after a formal investigation was launched by the UN’s Committee on the Rights of Persons with Disabilities, according to the Sunday Herald.

The Chingford and Woodford Green MP’s Department for Work and Pensions (DWP) has faced persistent criticism over its welfare reform programme, with charities and campaigners claiming disabled people have been hit the hardest by cuts to services and changes to benefits.

Last week, it was revealed that 2,380 people died between December 2011 and February 2014 after being declared “fit for work”, and therefore entitled to fewer benefits.

Bill Scott, director of policy at disability group Inclusion Scotland, told the Herald: “The UN have notified us they will be visiting Britain to investigate... and want to meet with us when they come, sometime in the next few months.”

Campaigners called for a review of the controversial sickness benefit assessments last week after the statistics revealed the number of deaths of benefit claimants.

The DWP said no "causal link" could be drawn from the data between an individual's benefit status and their likelihood of dying.

Overall, death rates for unemployed claimants had remained in line with trends in the wider population for a decade, it said.

But charities and unions, who claim the work capability assessment system is unfair and causes undue stress for vulnerable people, said the mortality rate appeared surprisingly high for people of working age who had been declared fit.

The UN investigation follows the revelation that Mr Smith’s department used fake quotes to support benefit cuts on a leaflet.

Following a Freedom of Information (FoI) request by website Welfare Weekly, it was revealed that stock images and fake quotations were used to illustrate supposed claimants' support for sanctions.

An online petition calling for the MP to resign has since gained 86,706 signatures in less than two weeks.