Thousands of disabled people and their families and supporters will converge on Westminster this week to protest against government cuts and their impact on key benefits such as the disability living allowance and the employment and support allowance. Afterwards they will lobby MPs as the welfare reform bill reaches a critical stage in the House of Commons.

Wednesday's protest, dubbed the Hardest Hit march, is being coordinated by hundreds of disabled people's organisations and charities and groups including Scope, Leonard Cheshire Disability, Mencap, the RNIB and Sense.

Organisers say that disabled people will be hit disproportionately hard by the cuts, which, they estimate, could result in families losing £9bn of support over the next four years.

Jaspal Dhani, chief executive of the United Kingdom Disabled People's Council, said the cuts would have an adverse effect on disabled people's rights and their ability to live independently. "We believe that disabled people stand to lose most from these cuts," he said. "We hope to show both the government and the community at large just how fearful disabled people are about the impact the cuts will have. It's about taking direct action because it seems government ministers are simply not listening."

Dhani said the cuts would result in disabled people being institutionalised and treated unfairly as local authorities try to save money by cutting funding to the bodies that support them.

Rebecca Rennison, co-chair of the Disability Benefits Consortium's policy group, agreed that disabled people were likely to feel the cuts far more keenly than the rest of the population.

"They're experiencing the same cuts as everyone else and then experiencing additional ones, so it's cuts on top of cuts," she said. "The disability living allowance (DLA) is vital to people's independence. They are taking away the mobility component that pays for things like taxis and allows people to get out of their homes. The impact will be devastating and people are saying enough's enough. That's why people from all over the country are coming to London to make their views known."

The rally will begin on Victoria Embankment on Wednesday morning and move to Westminster. Protesters will then lobby MPs in Westminster Hall and Methodist Central Hall. between 13.30 and 17.30.