Millions of people could be owed thousands of pounds in backpay due to a court case between the UK Government and some benefits claimants.
People on universal credit (UC) received a £20 weekly increase from the Department for Work and Pensions (DWP) from April 2020 to October 2021 to help them pay for additional costs incurred during the coronavirus crisis and subsequent lockdowns.
However, this uplift was not extended to those on older benefits such as employment support allowance (ESA), income support and jobseeker's allowance (JSA), Birmingham Live reports, which campaign groups said disproportionately affected disabled people.
Read more: All the new benefit and pension rates in full as MPs approve universal credit changes
Two disabled people on ESA launched the original legal challenge, and were subsequently joined by claimants on income support and JSA.
Around 2.4 million people would be in line to receive the extra cash if the High Court rules in favour of the benefits claimants.
Osborne's Law, representing the claimants, says they argue "the failure to extend the uplift to those on ESA unlawfully discriminated against them as disabled people contrary to the European Convention on Human Rights."
It added: "The claimants argue that it has become increasingly untenable for those claimants on legacy benefits to be treated differently from those on UC as they all face the same consequences of the pandemic.
"To continue to exclude those from legacy benefit from the uplift is risking the establishment of a two-tier social security system."
Disabled people and campaigners gathered outside the Royal Courts of Justice last November in support of the case.
Members of Disabled People Against Cuts (DPAC) and the Disability Benefits Consortium (DBC) - a network of over 100 organisations including Z2K, the MS Society, MND Association, and Leonard Cheshire - held a rally to demand justice for those who were denied extra support.
Lynn Pinfield, 51, from West Lothian, was diagnosed with multiple sclerosis (MS) in 2018 and is unable to work as a result of her condition.
She claims ESA, so was denied the £20 lifeline given to UC claimants.
In a statement ahead of the hearing, she said: "I absolutely think this is a case of discrimination against disabled people, and the High Court should find it unlawful.
"Everyone on benefits should be treated equally. They have made me feel like disabled people don't matter.
"During the pandemic, prices were steadily increasing but benefits remained the same, which was a struggle.
"With everyone at home all the time, our bills soared - our electricity bill doubled - and I've had to pay it all myself with no extra support."
And campaign groups have called on the government to offer claimants on these benefits the same uplift as UC claimants.
Anastasia Berry, of the DBC and MS Society, said: "MS is relentless, painful and disabling, and many with the condition rely on benefits such as ESA as they are unable to work.
"It is utterly disgraceful that at the height of the pandemic, when disabled people needed help the most, the Government turned their backs.
"Not only was this decision cruel, but it is clear that denying one group of people extra financial support is discriminatory and creates a two-tier social security system.
"That's why we are demanding justice for those who were discriminated against, and are calling for people on legacy benefits to receive a back-dated payment of the equivalent amount given to those on Universal Credit."
Ella Abraham, of Z2K and the DBC, said: "For the last 18 months millions of disabled people, single parents and others on legacy benefits have been discriminated against and struggled to put food on the table without the £20 a week increase those on Universal Credit received.
"We want to see back-dated payments for all those on legacy benefits who struggled to pay for essentials during the pandemic."
Lawyers representing the claimants at the hearing issued an update in December saying: "Judgement is awaited in the case. It is not unusual that in a case of this type and importance for many hundreds of thousands of people that judgement takes some time.
"Please be assured that as soon as judgement is handed down it will be communicated. In the meantime, please bear with us."
Since that time, there has been no further updates giving an indication of on when a ruling is expected.
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