Three disabled activists who took the government to court in an unsuccessful bid to stop the closure of the Independent Living Fund (ILF) have called on Labour MPs to halt their attempts to topple their party leader.

Anne Pridmore, Gabriel Pepper and Stuart Bracking have pointed out that Labour leader Jeremy Corbyn had been “unstinting” in his support for ILF-users throughout the campaign to prevent the fund’s closure.

The trio were joined by Paul Taylforth, the father of a fourth former ILF-user who was involved in the court cases, in raising concerns about developments within the party.

They sent an email outlining their concerns to Corbyn, deputy party leader Tom Watson, the shadow chancellor John McDonnell, the present and previous shadow ministers for disabled people, Debbie Abrahams and Kate Green, and Neil Coyle, a Labour MP and a former director of Disability Rights UK.

They pointed out that Corbyn issued a statement on the day ILF closed in June last year pledging to campaign for it to be reinstated.

Their court bids to overturn the government’s decision to close the fund were finally defeated in December 2014, prompting Tracey Lazard, chief executive of Inclusion London, to suggest that the move signalled “the end of the right to independent living for disabled people in the UK”.

They said in this week’s statement: “The democratic election of Jeremy Corbyn last September instilled hope among many disabled people and their families that the Labour party had turned a corner, and would campaign hard to stop further austerity and cuts to public services and benefits.

“A number of judicial reviews brought in recent years reflect the impact public service cuts are having on the lives of disabled people and their families.

“While legal challenges are sometimes successful, they cannot achieve the impact and change an effective political campaign can.

“Rather than sow further division, we would urge Labour MPs to remember who austerity and public sector cuts are hitting the hardest, and the lives now being destroyed by them.”

They said there was a “desperate need for unity” among working-class people and said the Labour party and its MPs needed to “consider their responsibility and duty of care towards those who will continue to face the consequences if we fail to end austerity now”.

They said this would only be possible if the party united behind Corbyn’s leadership and worked with trade unions and disability campaigners to “build a political movement to achieve this”.

This week, Corbyn lost a vote of confidence among his own MPs by 172 votes to 40, and now faces a leadership challenge from former minister Angela Eagle.

Yesterday (Wednesday), the former ILF-users were joined in their call by Disabled People Against Cuts (DPAC), which issued its own appeal to Labour members to back Corbyn.

In a statement on its website, it praised the “unstinting support” that Corbyn and shadow chancellor John McDonnell had given to both DPAC and disabled people.

It said: “Both have spoken out and voted against every horror the Tories have imposed on disabled people.”

McDonnell has sent a message to DPAC, urging all of its members and supporters “to support Jeremy if there is a leadership election”, and calling on non-members to join the party so they can vote for him.

Only last month, research by Greater Manchester Coalition of Disabled People suggested that the government’s failure to ring-fence the funding it was handing to local authorities following the ILF closure was leading to a “postcode lottery” of support for former ILF-recipients.

ILF was funded by the Department for Work and Pensions, and by last year it was helping nearly 17,000 disabled people with the highest support needs to live independently.

But ministers decided it should be scrapped, promising instead that nine months’ worth of non-ring-fenced funding would be transferred to councils in England and to devolved governments in Wales and Scotland, to cover the period from its closure last summer to April 2016.

The Scottish government has set up its own ILF for existing recipients in Scotland, while the Welsh government has set up a ring-fenced, local authority-run grant scheme that will run until at least 31 March 2017.

The minister for disabled people, Justin Tomlinson, announced in February that the government would provide another four years of transition funding to local authorities in England in 2016-17 (£177 million), 2017-18 (£171 million), 2018-19 (£166 million) and 2019-20 (£161 million), but that the money would again not be ring-fenced.