Media playback is unsupported on your device Media caption Raquel Rolnik: "I didn't have any agenda before coming here"

Conservative chairman Grant Shapps has condemned as an "absolute disgrace" a UN official's critical comments on the government's housing benefit changes.

Mr Shapps said he would be writing to the UN secretary general to protest.

He claimed the UN official Raquel Rolnik failed to meet any ministers or officials, was biased and had wrongly called the "spare room subsidy" policy "the bedroom tax".

Ms Rolnik says her recommendation is for the policy to be suspended.

She rejected most of the criticisms made by Mr Shapps, although she did apologise for referring to the policy as the bedroom tax, telling the BBC she had done so because that was "what everyone has been calling it since I got here".

Under the government's benefit changes social tenants deemed to have more bedrooms than they need have had their housing benefit reduced since April.

Ministers say private sector renters do not get spare rooms free, and argue the change will save around £500m a year and free up much needed larger properties.

Ms Rolnik told BBC Radio 4's Today programme that she had received "hundreds of testimonies" and said there was a "danger of a retrogression in the right to adequate housing" in the UK.

She cited examples of disabled people, or grandmothers who were carers, and said the measure seemed to have been designed "without the human component in mind".

She said her recommendation was "that it should be suspended" to allow time to better assess the human rights implications, and so it could be redesigned.

Ms Rolnik, who is producing a report on adequate housing around the world for the UN human rights council, says she was in the UK for two weeks at the government's invitation.

Her visit included trips to London, Edinburgh, Glasgow, Belfast and Manchester.

'Abuse of process'

Mr Shapps, responding to her comments on Today, said that she had not been invited by ministers and "she has clearly come with an agenda".

"It is completely wrong and an abuse of the process for somebody to come over, to fail to meet with government ministers, to fail to meet with the department responsible, to produce a press release two weeks after coming, even though the report is not due out until next spring, and even to fail to refer to the policy properly throughout the report.

Media playback is unsupported on your device Media caption Conservative chairman Grant Shapps: Report is "biased and one sided"

"That is why I am writing to the secretary general today to ask for an apology and an investigation as to how this came about."

He also said that she came from a country, Brazil, "that has 50m people in inadequate housing".

In his letter to UN secretary general Ban Ki Moon, Mr Shapps urged the claims to be withdrawn and said: "By referring to the policy as the 'bedroom tax' and posing for photos receiving 'dossiers' from those opposed to ending the Spare Room Subsidy, I believe that Ms Rolnik has shown political bias.

"We would have hoped that Ms Rolnik would have taken the necessary steps to ensure that her report was based on all the information available to her from the Government before she declared her conclusions less than two weeks after her 'mission' began."

The Department for Work and Pensions later confirmed that Ms Rolnik, the UN special rapporteur on housing "had one meeting with a senior official at the DWP".

On Tuesday there was a further meeting "at which the findings were presented by the rapporteur". A spokesman said that at the start Communities Secretary Eric Pickles "popped in - it would be pushing it to call it a meeting".

'Toxic'

Shadow work and pensions secretary Liam Byrne said the policy should be dropped and said what was "shocking" was that the Conservatives were pushing ahead with "hated" changes which he said were primarily hitting disabled people.

Labour has not committed to scrapping the policy if it wins the next election. Mr Byrne told the BBC that he had to demonstrate it would have the money to reverse the changes: "I am working very hard... to show how and why this tax should be dropped."

Plaid Cymru welcomed the report, suggesting the benefit changes were one of the "most toxic policies for decades".

"The UK is a signatory to the International Covenant on Economic, Social and Cultural Rights," said Hywel Williams MP

"This means that Ms Rolnik's findings should carry weight within the British justice system and prompt the government to abandon this most inhumane of policies."