A group of MPs has written to ministers asking them to support "people with no recourse to public funds" during the coronavirus crisis.
The MPs want NRPF status, a condition to some migrants' right to remain in the UK that stops them receiving public money, to be temporarily removed.
It comes after another group of MPs wrote to the Treasury asking it to help charities providing frontline services.
The Treasury has been contacted for a response.
NRPF - "no resource to public funds" - status is given to some migrants as a condition of their leave to remain in the UK, and prevents them from receiving most government funded benefits.
The group of 98 MPs, including 76 from Labour. say that no one with NRPF status can access universal credit, leaving those who are self-employed with no support and unable to follow government advice on social distancing.
In their letter, co-ordinated by Labour MP Taiwo Owatemi, they write: "Our constituents across the country have written to us concerned about how they will get through this crisis without government help.
While we understand that their welfare typically falls within local government remit, it is quite clear that during this unprecedented health crisis we need national government direction and guidance on the issue."
They add: "It is also unclear whether funds provided from the Job Retention Scheme will extend to those without recourse to public funds.
"This could not only leave people at risk of destitution but also in a situation where following NHS guidance on self-isolation presents serious challenges and potentially far reaching, fatal consequences."
'Growing concern' for charities
Separately, 100 MPs and peers from seven different political parties asked the government to provide support for charities.
Great to be joined by over 100 MPs and Peers from 7 parties to urge further clarity + urgent action from UK Government @RishiSunak for charities who face £4.3 billion loss in income over next 12wks. Will play crucial role in fight against #Coronavirus and supporting communities. https://t.co/eAdagzsLnv pic.twitter.com/SRS6gRjSyA— Stephen Doughty MP / AS (@SDoughtyMP) March 21, 2020
Unlike restaurants and cafes, charities providing frontline services need to stay open, and so cannot transfer furloughed staff onto the government's wage scheme.
Meanwhile, the letter says charities are predicted to lose £4.3bn of income over the next 12 weeks, according to the charities body, the NCVO.
The letter, written by Labour MP Stephen Doughty, asks the government to "provide immediate emergency funding for frontline charities supporting the response to the coronavirus crisis,".
It calls for a "stabilisation fund for all charities," and the government to confirm that all charities will qualify for the government's wage scheme, and other measures designed to protect the voluntary sector.
The letter was sent on 21 March, and Mr Doughty says the Treasury is "aware of growing concern and working on solutions."
But he added: "I have warned them they need to provide urgent help. Every day counts."
He added that he understands the measures recommended in the letter are being looked at.
A spokesperson for the Treasury said: "The chancellor has outlined an unprecedented package of measures to protect millions of people's jobs and incomes as part of the national effort in response to coronavirus.
"But we also recognise that some charities are facing difficult decisions, and will not want to shut down their services at exactly the time those service are most needed.
"Our interventions mean that charities can defer their VAT bills, will pay no business rates for their shops next year, and can get a Business Interruption Loan and furlough staff where possible with the government paying 80% of their wages. We want to support people, businesses, and charities to get through this challenging time."