Groups representing disabled people are demanding urgent meetings with ministers after it was revealed that 1.6 million pensioners with disabilities will lose their winter fuel payments because of government cuts.

A pensioner struggles to keep warm at home. Photograph: Studio Romantic/Shutterstock

The figures were released by the Department for Work and Pensions on Friday evening, in answer to a freedom of information request, despite the government having said it had done no official impact assessment on the policy. The internal DWP analysis also suggested that nine in 10 pensioners aged between 66 and 79, and eight out of 10 over-80s would lose their allowance.

Since those over 80 receive a higher payment – £300 as opposed to £200 – they would take the greatest financial hit, the document said.

The analysis revealed that although people with disabilities were more likely to retain the payment, 71% – 1.6 million – would still lose their entitlement, despite their greater dependence on heating their homes.

The analysis also estimated that of the 880,000 pensioners entitled to pension credit but who do not claim the benefit, only 100,000 are expected to sign up to it as a result of a government campaign now under way, meaning about 780,000 pensioners on low incomes would continue to miss out.

Scope, the charity for disabled people, said it would be taking its case to Labour’s conference in Liverpool, opening next weekend, and would be looking for urgent meetings with relevant cabinet ministers.

James Taylor, Scope’s executive director of strategy and social change, said: “We are concerned by the Government’s decision on the winter fuel payment. We know it will make life harder for older disabled people. It’s true some disabled pensioners receive pension credit but there are an alarming number who will miss out this winter.

“Life already costs more when you’re disabled. Higher electricity bills because of medical equipment to power. Higher heating bills because of health conditions affected by the cold.

“Since the cost of living crisis, Scope’s helpline has heard from disabled people who are cutting back on everything they can. Going without heating, forgoing medical treatment. Sacrifices that put their health at risk.”

The prime minister and the chancellor have refused to back down after announcing that winter fuel payments would be restricted to the poorest pensioners, those on pension credit. But the issue is unlikely to go away with the conference season approaching before winter sets in.

On Sunday, as the Liberal Democrat conference opened in Brighton, work and pensions spokesperson Wendy Chamberlain renewed pressure on the government, saying: “Pensioners across the country are terrified that during a cost of living crisis, the government is set to strip desperately needed support away from the most vulnerable.”

For the Conservatives, Laura Trott, shadow chief secretary to the Treasury, said: “The publication of these analyses is a damning indictment of this entire Labour government.

“Not only do these reports confirm that thousands of pensioners will suffer this winter as a result of chancellor Rachel Reeves’s cold-hearted decision, but they were also hidden until after Labour forced their MPs to vote through this cut. It is a downright disgrace.”

The government said: “While it is not routine to publish advice as part of the development of policy, we have published the equality analysis on winter fuel payment eligibility.

“Our focus is on ensuring that those who should be claiming this support are receiving it alongside the wider support for vulnerable households, including the warm homes discount, worth £150, and household support fund to help people with the cost of living and energy bills.

“Over a million pensioners will continue to receive winter fuel payments and through our commitment to protect the triple lock those on the full new state pension will receive an extra £400 – twice the average winter fuel payment.”