A United Nations committee will hear from British disability campaigners that the Government is breaching the rights of disabled people and ignoring requests for information on key issues.
On Monday activists will tell the UN's Committee on the Rights of Persons with Disabilities (CRPD) that their previous concerns have only been met with complacent or evasive answers.
In October the CRPD reported that welfare reforms have led to "grave and systematic violations" of disabled people's rights, findings the Government said it strongly disagreed with.
The committee is now conducting a much wider investigation to assess the UK's progress in implementing the UN Convention on the Rights of Disabled People, as part of a periodic review all nations signed up to the convention must go through.
The Government said the UK is a world leader in disability rights and spends billions of pounds to support those with disabilities and health conditions every year.
However, Kamran Mallick, the chief executive of Disability Rights UK, said many of the Government's answers in its submission to the committee "have a tone of complacency at best and high-handed evasion at worst".
He said it has provided no evidence to show how it is supporting people to lead independent lives, while its description of the Equality Act and the Care Act "simply don't reflect the everyday experiences of disabled people in the UK".
Mr Mallick added: "Many disabled people and their families saw the UK's signature of the international convention as a vital milestone on the journey to true equality and the fulfilment that comes with leading independent, rounded lives.
"They now feel betrayed by the Government's failure to adhere to either the spirit or the letter of the convention.
"Small steps forward are more than outweighed by a raft of significant adverse measures, such as cruel and demeaning benefit changes and the extension of compulsory mental health treatment to the community."
Mr Mallick is set to tell the committee in Geneva that a range of Government policies and a lack of appropriate support and services from the NHS and local authorities mean the UK is breaching the human rights of many disabled people.
Many disabled people are unable to live the independent, fulfilling lives they could enjoy if the Government respected the convention, he will say.
CRPD's review will look at issues such as detentions under mental health legislation, employment, education, transport and housing.
Disability Rights UK and other groups will give verbal evidence to the committee on Monday.
The committee will question representatives from the UK and devolved governments later this week.
The Government says that as a share of GDP, the UK's public spending on disability and incapacity is higher than all other G7 countries bar Germany, while its focus has been on helping disabled people achieve their potential in the job market and wider society.
A spokesman said: "The UK is a recognised world leader in disability rights and equality, which is why we supported the development of the UN convention.
"Almost 600,000 disabled people have moved into work over the last four years and we spend over £50 billion a year to support disabled people and those with health conditions.
"This first periodic review will help build on our progress to empower disabled people in all aspects of their lives."
The committee's previous inquiry was instigated by the charity Disabled People Against Cuts, which contacted CRPD in 2012.
Other charities subsequently confirmed that they had also been in contact with the UN.
The UN's report highlighted the impact of changes to housing benefit entitlement, eligibility criteria for personal independence payments and social care, and the closure of the independent living fund.
However, then work and pensions secretary Damian Green rejected the report's findings, saying the document demonstrated "an outdated view of disability which is patronising and offensive".
He added: "The UN measures success as the amount of money poured into the system, rather than the work and health outcomes for disabled people."